Osteochondritis dissecans (OCD) primarily affects subchondral bone. Multiple drilling, fixation implant or autogenous osteochondral grafts are reported as treatment options. We present the midterm results of cases in which an OCD lesion was treated by osteochondral autograft transfer and drilling.
Materials and Methods:
Between 2002 and 2006, 14 knees with International Cartilage Repair Society (ICRS-OCD) type II and III lesions were treated in our clinic using osteochondral autograft transfer and drilling by arthroscopic or open surgery. The average age of our patients was 22.14 years (range 17-29 years) and average followup was of 24.3 months (range 11-40 months). Lesion type was ICRS type II in five patients (35.7%) and ICRS type III in nine patients (64.3%). In cases with ICRS-OCD type II lesions, in situ fixation was applied following circumferential multiple drilling, while mosaicplasty was done following debridement and multiple drilling in cases with ICRS-OCD type III lesion. Mosaicplasty was performed in the lesion area by an average of 2.5 (range 1-3) cylindrical osteochondral autografts. Patients were not allowed to perform loading activities for 3 weeks in the postoperative period; movement was initiated by using CPM device in the early phase; full range of motion was achieved in third week, and full weight bearing was permitted in 6 to 8 weeks
While 6 and 8 patients were classified preoperatively as fair and poor, respectively, according to Hughston scale, excellent and good results were obtained postoperatively in 10 and 4 patients, respectively. During the followup, no problems were detected in any of the patients in the regions where osteochondral graft was harvested.
Biologic fixation or mosaicplasty and drilling as a technique to treatment of the lesion in OCD by osteochondral autograft transfer has resulted in good and excellent clinical outcomes in our patients and it is considered that providing blood flow to subchondral bone by circumferencial drilling leads to an increase in the robustness of biological internal fixation and shortens the duration of recovery.
Osteochondritis dissecans; Hughston scale; knee; mosaicplasty
Data are lacking in the literature regarding the incidence of osteochondrosis (dissecans) [OC(D)] in relation to lameness evaluation in Dutch Warmblood horses. The objective of this retrospective study was to assess the incidence of radiological abnormalities consistent with osteochondrosis or osteochondrosis dissecans in 1,231 sound Dutch Warmblood (DW) horses presented for pre-purchase examination. Standardised (Dutch) pre-purchase examination protocols were evaluated. The pre-purchase examination included a clinical, lameness and radiological evaluation, performed at a private equine clinic in the Netherlands. Radiographical examination included views of the distal (DIP) and proximal (PIP) interphalangeal, metacarpo- and metatarsophalangeal (MCP/MTP), tarsocrural (TC) and femoropatellar (FP) joints. Radiographical evidence of OC(D) was found in 44.3% of clinically sound DW horses. In this study, 443 horses (36%, n = 1,231) had evidence of OCD and 102 horses (8.3%, n = 1,231) had evidence of OC on pre-purchase radiographs. The results also indicated that the TC joints were significantly more likely to be affected. A considerable number of horses did not demonstrate any lameness, although radiographs revealed OC(D).
Osteochondrosis; dissecans; lameness; pre-purchase; examination
Over a period of 7 years
(1987 – 1994), 24 cases of osteochondritis dissecans of the knee
were treated with self-reinforced polyglycolic acid (SR-PGA) and
polylactic acid (SR-PLLA) rods. Rods measuring 1.1 mm, 1.5 mm
and 2 mm in diameter, and 20 – 40 mm in length were used in the
fixation of the fragment depending on the size of the lesions.
There were 23 patients with osteochondritis dessicans in the
medial and 1 in the lateral femoral condyle. The average age of
the patients was 25 years (range: 16 – 48). Follow-up was for
3.3 years (range: 1 – 7.6). There were 6 lesions in situ, 3
early separations, 11 were partially detached, and there were 4
loose bodies. SR-PGA rods were used in 12 patients, SR-PLLA rods
in 11 patients, and both SR-PGA and SR-PLLA rods in 1 patient.
The rod in each case was inserted subchondrally and in 9 cases
arthroscopically, using a special instrument. In our study, the
clinical result was excellent in 13 patients, good in 6, fair in
1 and poor in 4. On radiological assessment the fragment had
healed in 19 cases. Synovitis occurred in 1 patient in the
SR-PGA group (1/13): the effusion continued for 6 months
postoperatively but, after treatment by needle aspiration, there
were no symptoms at follow-up 4.2 years later. We conclude that
SR-PGA and SR-PLLA rods can be used intra-articularly for the
adequate fixation of osteochondritis dissecans.
This study aimed to detect, by radiographic examination, the evolution of osteochondral lesions in the tarsocrural and femoropatellar joints of Lusitano foals. Within 1 month of age, 76.08% of foals had radiographic signs of osteochondrosis, but only 16.20% had lesions at 18 months. The radiographic signs resolved by 5 mo of age in most foals, but some cases that involved either joint, were not resolved until 12 mo of age. It is thought that the “age of no return” is 5 mo for the tarsocrural and 8 mo for the femoropatellar joint but this study demonstrated regression of osteochondral lesions in both joints of Lusitano foals up to 12 months of age.
Navicular bones from 74 horses were examined at necropsy. Animals ranged in age from eight months to 30 years. Eight horses had a clinical history of navicular disease. Degenerative lesions in the fibrocartilaginous surface of the navicular bone and of the surface of the deep flexor tendons were age related changes not necessarily related to lameness. These lesions were more extensive in horses with a history of navicular disease, and were often accompanied by adhesions and subchondral cavitation of the fibrocartilaginous surface of the navicular bone. Osteophytes, present in 12 of the 74 horses, appeared to be age-related and were uncommon in horses with a history of navicular disease. Nutrient foramina on the distal border of the navicular bone were highly variable in size and shape; in horses with a history of navicular disease they often had a small external opening that became larger as it penetrated the bone. Occlusive vascular disease (arteriosclerosis) was found in sound horses and in horses with a history of navicular disease. Thrombosis of arteries or ischemic necrosis of bone was not identified in any case.
The mechanisms and completeness of equine articular cartilage repair were studied in ten horses over a nine month period. Large (15 mm square) and small (5 mm square) full-thickness lesions were made in weight bearing and nonweight bearing areas of the radiocarpal, middle carpal and femoropatellar joints. The horses were euthanized in groups of two 1, 2.5, 4, 5 and 9 months later. Gross pathology, microradiography, and histopathology were used to evaluate qualitative aspects of articular repair. Computer assisted microdensitometry of safranin-O stained cartilage sections was used to quantitate cartilage matrix proteoglycan levels. Structural repair had occurred in most small defects at the end of nine months by a combination of matrix flow and extrinsic repair mechanisms. Elaboration of matrix proteoglycans was not complete at this time. Statistically better healing occurred in small weight bearing lesions, compared to large or nonweight bearing lesions. Synovial and perichondrial pannus interfered with healing of osteochondral defects that were adjacent to the cranial rim of the third carpal bone. Clinical and experimental experience suggests that these lesions are unlikely to heal, whereas similar lesions in the radiocarpal and femoropatellar joints had satisfactory outcomes. Observations made in this study support the use of early postoperative ambulation, passive flexion of operated joints, and recuperative periods of up to a year for large cartilage defects.
As the understanding of interactions between articular cartilage and subchondral bone continues to evolve, increased attention is being directed at treatment options for the entire osteochondral unit, rather than focusing on the articular surface only. It is becoming apparent that without support from an intact subchondral bed, any treatment of the surface chondral lesion is likely to fail. This article reviews issues affecting the entire osteochondral unit, such as subchondral changes after marrow-stimulation techniques and meniscectomy or large osteochondral defects created by prosthetic resurfacing techniques. Also discussed are surgical techniques designed to address these issues, including the use of osteochondral allografts, autologous bone grafting, next generation cell-based implants, as well as strategies after failed subchondral repair and problems specific to the ankle joint. Lastly, since this area remains in constant evolution, the requirements for prospective studies needed to evaluate these emerging technologies will be reviewed.
Cartilage repair; Autologous chondrocyte implantation; Microfracture; Subchondral bone
Records of two veterinary teaching hospitals from January 1, 1976 to June 1, 1982 were searched for diagnoses of stifle lameness. Forty-two records were found and information was recorded regarding signalment, history and clinical presentation. The following abnormalities were associated with stifle lameness: subchondral bone cyst (18 cases), joint instability (15 cases), degenerative joint disease (12 cases), cranial cruciate ligament injury (9 cases), cytological or bacteriological evidence of sepsis (9 cases), collateral ligament injury (3 cases), femorotibial luxation (2 cases) and intra-articular fracture (2 cases). The duration of lameness presentation ranged from 0.3 to 24 weeks and the mean follow-up period was 20.47 ± 11.44 months (three animals were lost to follow-up). Animals (n = 15) with subchondral bone cysts as the sole association with lameness presented at an early age (range — 6 to 18 months) and apparently regardless of treatment, had a good prognosis as determined by 75% (three lost to follow-up) returning to their intended function. Cattle (n = 9) with septic arthritis were presented at an age ranging from two months to seven years and only 22.2% returned to function. Cattle (n = 15) with joint instability presented at an age varying from nine months to 13 years also did poorly as only 26.6% returned to function.
Cattle; stifle; lameness; septic arthritis; subchondral bone cyst; degenerative joint disease
Culicoides hypersensitivity is a chronic, recurrent, seasonal dermatitis of horses that has a worldwide distribution, but has only recently been reported in Canada. It is characterized by intense pruritus resulting in lesions associated with self-induced trauma.
A survey of veterinarians and horse-owners in British Columbia showed no differences in susceptibility due to the sex, color, breed, or height of the horses. The prevalence of the disease in the 209 horses surveyed was 26%. Horses sharing the same pasture could be unaffected. The disease was reported primarily from southwestern British Columbia; it occurred between April and October and usually affected the ventral midline, mane, and tail. Horses were generally less than nine years old when the clinical signs first appeared ([unk]=5.9 yr). Culicoides hypersensitivity was common in the lineage of several affected horses, possibly indicating a genetic susceptibility. Most cases were severe enough to require veterinary attention and some horses were euthanized.
Degenerative suspensory ligament desmitis (DSLD) is a debilitating disorder thought to be limited to suspensory ligaments of Peruvian Pasos, Peruvian Paso crosses, Arabians, American Saddlebreds, American Quarter Horses, Thoroughbreds, and some European breeds. It frequently leads to persistent, incurable lameness and need to euthanize affected horses. The pathogenesis remains unclear, though the disease appears to run in families. Treatment and prevention are empirical and supportive, and not effective in halting the progression of the disease. Presently, the presumptive diagnosis of DSLD is obtained from patient signalment and history, clinical examination, and ultrasonographic examination of clinically affected horses, and is confirmed at post mortem examination. Presently, there are no reliable methods of diagnosing DSLD in asymptomatic horses. The goal of this study was to characterize and define the disorder in terms of tissue involvement at the macroscopic and microscopic levels.
We examined tissues and organs from 28 affected horses (22 Peruvian Pasos, 6 horses of other breeds) and from 8 control horses. Histopathological examination revealed the presence of excessive amounts of proteoglycans in the following tissues removed from DSLD-affected horses: suspensory ligaments, superficial and deep digital flexor tendons, patellar and nuchal ligaments, cardiovascular system, and sclerae. Electron microscopy demonstrated changes in diameters of collagen fibrils in the tendon, and in smooth muscle cells of the media of the aorta compatible with increased cell permeability in DSLD-affected cells. Separation of tendon extracts by gel chromatography revealed the presence of additional proteoglycan(s) in extracts from affected, but not control extracts.
This study demonstrates for the first time that DSLD, a disease process previously thought to be limited to the suspensory ligaments of the distal limbs of affected horses, is in fact a systemic disorder involving tissues and organs with significant connective tissue component. Abnormal accumulation of proteoglycans between collagen and elastic fibers rather than specific collagen fibril abnormalities is the most prominent histological feature of DSLD. Because of this observation and because of the involvement of many other tendons and ligaments beside the suspensory ligament, and of non-ligamentous tissue we, therefore, propose that equine systemic proteoglycan accumulation or ESPA rather than DSLD is a more appropriate name for this condition.
Osteochondral defects of the ankle can either heal and remain asymptomatic or progress to deep ankle pain on weight bearing and formation of subchondral bone cysts. The development of a symptomatic OD depends on various factors, including the damage and insufficient repair of the subchondral bone plate. The ankle joint has a high congruency. During loading, compressed cartilage forces its water into the microfractured subchondral bone, leading to a localized high increased flow and pressure of fluid in the subchondral bone. This will result in local osteolysis and can explain the slow development of a subchondral cyst. The pain does not arise from the cartilage lesion, but is most probably caused by repetitive high fluid pressure during walking, which results in stimulation of the highly innervated subchondral bone underneath the cartilage defect. Understanding the natural history of osteochondral defects could lead to the development of strategies for preventing progressive joint damage.
Osteochondral defect; Cartilage; Ankle joint; Subchondral cyst; Natural history; Pain
The use of monoiodoacetate (MIA) for arthrodesis of the proximal interphalangeal joint (PIJ) and the effect of exercise on the degree of fusion were investigated. Eight horses received 3 injections (Weeks 0, 3, 6) of MIA (2 mL; 60 mg/mL) into the right or left front PIJ. Peri-operatively, the horses received phenylbutazone, butorphanol, and abaxial sesamoidean nerve blocks to relieve pain. During the study, the horses were monitored for general health, lameness, and swelling around the injection area. Radiographs were taken biweekly to evaluate bony fusion. Horses were randomly divided into non-exercised and exercised groups. Exercise consisted of 20 minutes of trotting on a treadmill (4 m/s), 3 days per week for 13 weeks. The horses were euthanized at 24 weeks. Slab sections of the PIJ were evaluated grossly and radiographically for bony fusion. Histologic examinations were performed to evaluate articular cartilage. Three horses were excluded from the study after developing soft tissue necrosis around the injection site, septic arthritis, and necrotic tendinitis. The remaining horses remained healthy, developed a grade 1 to 4 lameness with minimal to severe swelling in the PIJ region. All 5 horses showed radiographic evidence of bony fusion, however, no fusion was present when injected joints were examined on postmortem examination. Histologic examination revealed thinning of the cartilage, diffuse necrosis of chondrocytes, with the calcified zone intact. Subjectively, exercise did not influence the degree of cartilage destruction. Based on this study, chemical arthrodesis cannot be advocated in clinical cases because of the high complication rate and lack of bony fusion.
Osteoarthrosis (OA) of the antebrachiocarpal joint from 7 riding horses is described. The horses were old mares and developed severe OA, with ankylosis in some of the joints. The lesions were bilateral, and the owners noticed the lameness in a late event. The cause of severe OA in these mares is not clear. The fact that OA was bilateral indicates that a single traumatic injury is unlikely as an etiologic factor. Considering the severe joint lesions it took long time before the horse-owners noticed the lameness. It is discussed if the threshold of pain is higher in the antebrachiocarpal joint compared with the middle carpal joint.
The objective of this study was to examine all kick injuries to the radius and tibia seen in an ambulatory setting over an 11-year period in order to determine factors affecting outcome. Medical records of 51 horses seen for a kick injury to the radius or tibia were reviewed. Signalment, physical examination findings, type of management, and outcome were evaluated. There was a significant association between the presence of bony crepitus and a lameness score of ≥ 4/5 and a poor outcome. There was no relationship between signalment and outcome, but significantly more Thoroughbred/Thoroughbred cross horses were affected than any other breed. There was no detected relationship between the type of management and outcome; however, most (81%) horses were managed on stall rest. Horses with bony crepitus or with a lameness score of ≥ 4/5 were at an increased risk for euthanasia.
Osteochondritis dissecans of the knee primarily affects subchondral bone, with a secondary effect on the overlying articular cartilage. This process can lead to pain, effusions, and loose body formation. While stable juvenile lesions often respond well to nonoperative management, unstable juvenile lesions, as well as symptomatic adult lesions, often require operative intervention. Short-term goals focus on symptomatic relief, while long-term expectations include the hope of preventing early-onset arthritis. Surgical options include debridement, loose body removal, microfracture, arthroscopic reduction and internal fixation, subchondral drilling, osteochondral autograft or allograft transplantation, and autologous chondrocyte implantation. Newer single-stage cell-based procedures have also been developed, utilizing mesenchymal stem cells and matrix augmentation. Proper treatment requires evaluation of both lesional (size, depth, stability) and patient (age, athletic level) characteristics.
Osteochondritis dissecans; Knee; Microfracture; Osteochondral autologous transplant; Drilling; Internal fixation; Allograft; Autologous chondrocyte implantation; Loose body; Surgical treatment; Cartilage
Osteochondritis dissecans lesions occur frequently in children and adolescents. Treatment can be challenging and depends on the status of the articular cartilage and subchondral bone. Injection of calcium phosphate bone substitute into the area of subchondral bone edema (Subchondroplasty; Knee Creations, West Chester, PA) may be an option. We present a case of a lateral tibial plateau osteochondritis dissecans lesion treated with subchondral injection of nanocrystalline calcium phosphate. Preoperative magnetic resonance imaging is used to determine the area of subchondral edema, and intraoperative fluoroscopy is used to localize this area with the injection cannula. Calcium phosphate is injected by use of a series of syringes until the appropriate fill is obtained. Treatment of concomitant cartilage defects may also be carried out at this time.
The lame sire, unsound for breeding, can cause substantial economic loss due to reduced pregnancies in the beef-producing herd.
To test the hypothesis that joint disorder is a possible cause of infertility in beef sires, right and left hind limb bones from 34 beef sires were examined postmortem to identify lesions in the femorotibial, femoropatellar (stifle), tarsocrural, talocalcaneus, and proximal intertarsal (tarsal) joints. The bulls were slaughtered during or after the breeding season due to poor fertility results. Aliquots of the cauda epididymal contents taken postmortem from 26 bulls were used for sperm morphology evaluation. As a control, hind limbs (but no semen samples) from 11 beef bulls with good fertility results were included.
Almost all infertile bulls (30/34) had lesions in at least one joint. Twenty-eight bulls (28/30, 93%) had lesions in the stifle joint, and 24 (24/28, 86%) of these were bilateral. Fourteen bulls (14/30, 47%) had lesions in the tarsal joint, and 10 (10/14, 71%) of these were bilateral. Four bulls (4/34, 12%) had no lesions, three bulls (3/34, 9%) had mild osteoarthritis (OA), 5 (5/34, 15%) moderate OA, 17 (17/34, 50%) severe OA and 5 (5/34, 15%) deformed OA. Almost all OA lesions (97%) were characterized as lesions secondary to osteochondrosis dissecans. All the bulls with satisfactory sperm morphology (n = 12/34) had joint lesions, with mostly severe or deformed bilateral lesions (83%). Consequently, the most likely cause of infertility in these 12 bulls was joint disease. Almost all control bulls (10/11) had OA lesions, but most of them were graded as mild (55%) or moderate (36%). None of the control bulls had severe lesions or deformed OA.
We suggest that joint lesions should be taken into consideration as a contributory cause of reproductive failure in beef sires without symptoms of lameness.
Osteochondritis dissecans (OCD) of the capitellum is most often seen in adolescents who participate in sports that involve repetitive loading of the elbow. Unstable defects typically require surgical intervention that involves fragment fixation, debridement, or reconstruction with an osteochondral autograft transfer. Optimum surgical management of unstable defects remains controversial.
Type of Study:
Relevant articles published after 1992 were identified using MEDLINE, the EMBASE database, and the Cochrane Library.
Both debridement and osteochondral autograft transfer for treatment of capitellar OCD lesions result in good short- and midterm outcomes with a high rate of return to sports. Larger defects involving more than 50% of the articular surface or involving the lateral margin of the capitellum may have worse outcomes after debridement and may be better treated with fragment fixation or osteochondral autograft transfer.
High-level evidence is lacking to determine the superiority of debridement or osteochondral autograft transfer for the treatment of capitellar OCD lesions. A prospective longitudinal multicenter study, using validated outcome measures, that enrolls a large number of patients is needed to establish optimal treatment for unstable capitellar OCD lesions.
osteochondritis dissecans; elbow; capitellum
A lateral or medial angulation of the shaft of the distal tibiotarsal bone resulting in deviation of the lower part of the leg and frequently with bending of the proximal shaft of the tarsometatarsus is the most common leg deformity in broiler chickens. This lateral or medial deviation of the legs in broiler chickens, which has been described by many workers, deserves a specific name such as angular bone deformity or valgus-varus deformity of intertarsal joint, so that it may be separated from other varieties of lameness in broilers.
Broiler chicken; leg deformity; valgus-varus
The purpose of the study was to identify factors influencing the outcome and prognosis of rupture of the tendon of the peroneus tertius muscle in 27 horses. Information on history, physical examination findings, diagnosis, treatment, and final outcome was summarized from medical records. Long-term follow-up information on horses was obtained by telephone survey. A stepwise logistic regression model was used to analyze factors influencing the outcome. Rupture occurred in the midbody of the tendon in 11 horses, at the insertion site in 11 horses, and at the origin in 2 horses. Overall, 18/23 (78.3%) horses returned to their previous level of exercise, 5/23 (21.7%) horses were euthanized due to persistent lameness. If the horse was racing at the time of injury or had an additional structure injured besides the peroneus tertius tendon, it was less likely to return to its intended use.
A survival analysis was used to compare the culling rate of Icelandic horses due to the presence of radiographic and clinical signs of bone spavin. A follow-up study of 508 horses from a survey five years earlier was performed. In the original survey 46% of the horses had radiographic signs of bone spavin (RS) and/or lameness after flexion test of the tarsus. The horse owners were interviewed by telephone. The owners were asked if the horses were still used for riding and if not, they were regarded as culled. The owners were then asked when and why the horses were culled. During the 5 years, 98 horses had been culled, 151 had been withdrawn (sold or selected for breeding) and 259 were still used for riding. Hind limb lameness (HLL) was the most common reason for culling (n = 42). The rate of culling was low up to the age of 11 years, when it rose to 0.05 for horses with RS. The risk ratio for culling was twice as high for horses with RS compared with horses without RS and 5.5 times higher for culling because of HLL. The risk of culling (prognostic value) was highest for the combination of RS with lameness after flexion test, next highest for RS and lowest for lameness after flexion test as the only finding.
It was concluded that bone spavin affects the duration of use of Icelandic horses and is the most common cause of culling due to disease of riding horses in the age range of 7–17 years.
Icelandic horses; bone spavin osteoarthroses; survival analysis; questionnaire
Subchondral metastasis is a rare occurrence and poses a diagnostic dilemma as initial films may show a lytic lesion in the subchondral region often misinterpreted as being benign.. We present five cases of subchondral metastasis as well as a review of the literature. In our cases, we present subchondral metastasis in the elbow, shoulder, and hip joints. All patients had pain over the affected joint and most presented with a lytic lesion in the subchondral bone. Three patients have died since presentation and two are doing well at last follow up visit. Subchondral metastasis is a rare entity, but it should be included in the differential of a lytic lesion in the subchondral bone.
Osteochondritis dissecans (OCD) of the femoral condyle is a rare lesion.
Materials and methods
A retrospective study (level IV evidence) analyzing a series of 40 pediatric cases with juvenile femoral condyles osteochondritis treated by arthroscopic multiple transchondral drilling between February 1999 and June 2008 was undertaken. This lesion affected the medial condyle in 87.5% of cases. The average age at treatment was 13.4 years. Our study took into account the location of the lesion and its radiological evolutionary stage. The average follow up was 14.8 months. The postoperative evaluation was based on the clinical and radiological scores of Hughston.
Good clinical and radiological results in 97.5 and 95% of cases,
respectively were obtained, with a significant correlation (P < 0.001) between clinical scores and radiological Hughston scores. The closed nature of the growth plate during surgery has a significant deleterious effect (P < 0.001) on the clinical and radiological score of Hughston.
All patients presenting juvenile condylar osteochondritis with open growth plate during treatment had good clinical and radiological results, confirming the validity and effectiveness of multiple transchondral drilling in this type of lesion.
Juvenile osteochondritis dissecans; Femoral condyles; Arthroscopic transchondral drilling
It is unknown what causes donor site morbidity following the osteochondral autograft transfer procedure or how donor sites heal. Contact pressure and edge loading at donor sites may play a role in the healing process. It was hypothesized that an artificially created osteochondral defect in a weightbearing area of an ovine femoral condyle will cause osseous bridging of the defect from the upper edges, resulting in incomplete and irregular repair of the subchondral bone plate.
To simulate edge loading, large osteochondral defects were created in the most unfavourable weightbearing area of 24 ovine femoral condyles. After killing at 3 and 6 months, osteochondral defects were histologically and histomorphometrically evaluated with specific attention to subchondral bone healing and subchondral bone plate restoration.
Osteochondral defect healing showed progressive osseous defect bridging by sclerotic circumferential bone apposition. Unfilled area decreased significantly from 3 to 6 months (P = 0.004), whereas bone content increased (n.s.). Complete but irregular subchondral bone plate restoration occurred in ten animals. In fourteen animals, an incomplete subchondral bone plate was found. Further common findings included cavitary lesion formation, degenerative cartilage changes and cartilage and subchondral bone collapse.
Osteochondral defect healing starts with subchondral bone plate restoration. However, after 6 months, incomplete or irregular subchondral bone plate restoration and subsequent failure of osteochondral defect closure is common. Graft harvesting in the osteochondral autograft transfer procedure must be viewed critically, as similar changes are also present in humans.
Level of evidence
Prognostic study, Level III.
Donor site morbidity; Osteochondral autograft transfer; Subchondral bone plate
A total of 43 horses were used for the study of the pharyngeal bacterial flora. The median value of the number of bacteria in the group of 19 normal horses was 3.8 × 104 cfu/g of secretions. This value was 6.4 × 104cfu/g in horses with grade I pharyngitis, 1.3 × 105 cfu/g in horses with grade II pharyngitis and 3.5 × 106 cfu/g in horses affected with grades III and IV pharyngitis. Corynebacterium spp, coagulase-negative staphylococci, Nocardia spp, Moraxella spp and Enterobacter spp were the most frequently encountered bacteria in the normal animals as well as in horses affected with pharyngitis of grades I or II. Moraxella spp were isolated in 87.5% of the horses with pharyngitis of grades III and IV, followed by Streptococcus zooepidemicus, Pseudomonas aeruginosa, coagulase-negative staphylococci and Enterobacter spp. No fastidious bacteria, nor strict anaerobes were isolated from any of the 43 horses. None of the microorganisms were found in 100% of the animals and the majority of the isolates were opportunistic bacteria. These results demonstrate that the isolation of Moraxella spp and S. zooepidemicus in large numbers is frequent in horses with lymphoid follicular hyperplasia grades III and IV. Fungi were isolated in small numbers from two or three horses in each group.
Horses; pharyngitis; bacterial flora