Successful Management of Severe Open Metacarpophalangeal Joint Dorsal Luxation in a Horse

A 3-year-old Darreh-Shuri stallion was presented with left forelimb open dorsal fetlock luxation immediately after being hit by a motorized vehicle. The horse was in a non–weight-bearing position on the affected limb. General physical examination revealed normal vital parameters and no special concurrent abnormality. Radiographic examination in lateromedial and dorsopalmar views of the affected limb showed complete luxation of the metacarpophalangeal joint with no fractures. Ultrasonographic evaluation revealed intact collateral ligaments. Under general anesthesia and following routine preparations, forceful manual pressure was exerted on the distal part of the metacarpus and proximal part of the first phalanx to reduce the luxation. Joint capsule and skin laceration were sutured. Intraarticular amikacin (500 mg) was administered and repeated on the third and fifth days postoperatively. A palmar polyvinyl chloride, synthetic plastic polymer (PVC) splint was placed following adequate padding from the carpus to the toe. The higher and lower third of the splint was casted and the middle part left open to manage the joint and skin lesion. Intraarticular sodium hyaluronate (20 mg) was administered 10 days later. After cast removal following 5 weeks, the stallion revealed no sign of lameness. The owner was instructed to keep the stallion confined to a stall for at least 2 more months with a restricted daily short hand walk. Special casting methods for immobilization of a limb with an open joint luxation can tremendously improve the healing process.     

A Modified Cloward''s Technique for Arthrodesis of the Normal Metacarpophalangeal Joint in the Horse

A modified Cloward's technique was performed for arthrodesis of one metacarpophalangeal (MCP) joint in eight horses. Dorsal arthrotomies were performed medial and lateral to the common digital extensor tendon and two 16 mm holes were drilled through the joint. A perforated cylindrical stainless steel basket filled with cancellous bone was impacted into each hole. The limbs were supported in casts for 8 weeks. The joints were examined and radiographed at 4 weeks, 8 weeks, 6 months, and 10 months. One horse was euthanatized at week 14 to assess the progress of the arthrodesis. In the other seven horses, there was clinical fusion at month 6. Dynamographic evaluations were performed 11 months after surgery at the walk and trot. The maximum vertical forces exerted during weight bearing by treated and control limbs were compared. No difference was detected at the walk; however, a significant difference was present at the trot (p less than 0.05). It was calculated that at the trot the horses placed 90% as much force on the treated limb as on the control limb. Eleven months after surgery, the baskets contained compact and cancellous bone. Ingrowth of bone occurred through all openings, completely filling the baskets and fusing the joints.     

Surgical Excision of Soft Tissue Fibrosarcomas in Cats

Objective — The purpose of this study was to determine the tumor-free interval and survival times of cats who had one (group 1) or more (group 2) surgeries, or surgery and radiation therapy (RTH) (group 3) for treatment of soft tissue fibrosarcomas (FSA).
Study Design — Retrospective study.
Animals or Sample Population — 45 client-owned cats.
Methods — Medical records of cats with soft tissue FSA were examined. Vaccination and feline leukemia virus (FeLV) status, age, sex, breed, tumor location, number of surgeries, completeness of excision, and histopathological grade were evaluated to correlate with tumor-free interval and survival periods.
Results — Overall median tumor-free interval and survival times were 10 and 11.5 (range, 1 to 40) months. Median tumor-free interval and survival times were more than 16 months each in group 1, more than 5 and 13 months in group 2, and 4.5 and 9 months in group 3. Age, sex, breed, vaccination or FeLV status, tumor location, or histopathological grade did not affect median tumor-free interval or survival times ( P <.05). Cats with complete excisions had significantly longer median tumor-free interval (>16 versus 4 months) and survival time (>16 versus 9 months) than those with incomplete excisions ( P =.008). Radiation therapy did not seem to extend tumor-free interval and survival times ( P =.013). However, most group 3 cats had incomplete surgical excisions, resulting in recurrent or progressive disease.
Conclusions — Complete surgical excision of FSA in cats is possible and can be curative.
Clinical Relevance — Aggressive surgical excision with wide margins appears to contribute to extended tumor-free interval and survival times in cats with soft tissue FSA. Controlled prospective studies are needed to determine the efficacy of RTH in treatment.     

Lameness Associated with Coxofemoral Soft Tissue Masses in Six Dogs

Six cases of mechanical lameness involving the coxofemoral joint are presented. All dogs had a history of chronic rear leg pain and lameness, and decreased range of motion of the hip. On physical examination, ventral subluxation of the coxofemoral joint during extension was present in three dogs. A radiographic diagnosis of subluxation was made in five dogs. In each dog, surgical exploration of the area caudal to the coxofemoral joint revealed a fibrous mass between the lesser or third trochanters and the ischium, diagnosed as a nonneoplastic fibrous reaction by microscopic examination. The clinical, radiographic, and histopathologic signs were similar to previously described cases of myositis ossificans. Five dogs returned to normal function after excision of the soft tissue mass, and one dog was normal when lost to follow-up 4 weeks postoperatively.     

Excision of Cutaneous Tumors in the Horse Using Histologic Guidance

A highly successful surgical technique for removing cutaneous tumors in humans was used in seven horses with cutaneous squamous cell carcinoma (n = 3) or sarcoid (n = 4). In humans, the complete underside of the tumor is evaluated histologically by processing horizontal sections from the tumor base, and orientation between the wound surface and the undersurface of the excised tumor is maintained by mapping both surfaces. The technique ensures that small foci of residual tumor can be located accurately and removed. Based on our experience, three modifications of the human technique are suggested for its use in horses. The equine patient should be placed under general anesthesia rather than using local anesthesia if the tumor is in a difficult position for standing surgery or the patient is uncooperative; useful information can be obtained from tissue processed in buffered formalin if frozen sections are not available; and optimal tumor size for this procedure is no larger than 3 x 2 cm.     

Excision of Oral Squamous Cell Carcinoma in a Horse

A large oral squamous cell carcinoma in a 27-year-old Arabian stallion was removed by partial excision of the incisive bone. There was no gross evidence of recurrence or metastasis 5 months later.     

Metacarpophalangeal Joint Synovial Pad Fibrotic Proliferation in 63 Horses

Medical records, radiographs, and sonograms of 63 horses with metacarpophalangeal joint synovial pad proliferation were examined retrospectively. All horses had lameness, joint effusion, or both signs associated with one or both metacarpophalangeal joints. Bony remodeling and concavity of the distodorsal aspect of the third metacarpal bone (Mc3) just proximal to the metacarpal condyles was identified by radiography in 71 joints (93%); 24 joints (32%) had radiographic evidence of a chip fracture located at the proximal dorsal aspect of the proximal phalanx. Fifty-four joints (71%) were examined by ultrasound. The mean ± SD sagittal thickness of the synovial pad was 11.3 ± 2.8 mm. Seventy-nine percent of the horses had single joint involvement with equal distribution between the right and left forelimbs. Sixty-eight joints in 55 horses were treated by arthroscopic surgery. Sixty joints (88%) had debridement of chondral or osteochondral fragmentation from the dorsal surface of Mc3 beneath the synovial pad and 30 joints (44%) had a bone chip fracture removed from the medial or lateral proximal dorsal eminence of the proximal phalanx. Complete or partial excision of both medial and lateral synovial pads was completed in 42 joints. Only the medial synovial pad was excised or trimmed in 21 joints, and 5 joints had only the lateral pad removed. Eight joints in eight horses were treated by stall rest, administration of intra-articular medication and systemic nonsteroidal anti-inflammatory drugs. Follow-up information was obtained for 50 horses treated surgically and for eight horses treated medically. Forty-three (86%) that had surgery returned to racing; 34 (68%) raced at an equivalent or better level than before surgery. Three (38%) of the medically treated horses returned to racing; only one horse raced better than the preinjury level. Horses that returned to racing at a similar or equal level of performance were significantly younger in age than horses returning at a lower level or not racing (P≤.05). Overall, horses with synovial pad proliferation treated by arthroscopic surgery had a good prognosis for return to racing at a level equal or better than before injury.     

Evaluation of Lameness Associated with Arthroscopy and Arthrotomy of the Normal Canine Cubital Joint

OBJECTIVE: To evaluate gait, range of motion (ROM), and lameness in normal dogs after arthroscopy or arthrotomy of the cubital joint. STUDY DESIGN: Experimental study. ANIMALS: Fourteen mature, healthy dogs. METHODS: Dogs were randomly assigned to treatment groups. Seven underwent arthrotomy and 7 underwent arthroscopy of the left cubital joint. Dogs were evaluated using kinetic gait assessment, subjective evaluation scores, and cubital joint ROM. Evaluations were performed before and on days 2, 4, 7, 15, 22, and 29 after surgery. Radiographs made before and after the surgical procedures were evaluated. RESULTS: Significant differences in peak vertical force and vertical impulse force were not observed between surgery groups (P =.88 and.49, respectively). Joint ROM was not significantly different between groups (P =.09 for flexion and.91 for extension). For all dogs, joint ROM and radiographic evaluations remained normal throughout the study period. Significant differences in subjective lameness scores, weight bearing, or pain were not observed between groups (P >/ or =.19 for all variables). CONCLUSIONS: In this study population, significant differences between dogs undergoing arthroscopy or arthrotomy of the cubital joint with respect to postoperative pain, weight bearing, joint ROM, or temporal improvement of ground reaction forces were not observed. CLINICAL RELEVANCE: The results of this study suggest that postoperative morbidity should not be a factor when making a decision to perform either arthroscopy or arthrotomy for exploration of the medial compartment of the canine cubital joint.     

Volume of the Synovia in Certain Joint Cavities in the Horse

A method of determining the volumes of synovia in certain articular cavities in the horse is described. The method is based on the degree of dilution of human serum albumin labelled with ¹²⁵I that is injected into the joint. It is shown that uniform distribution of the injected substance is attained within 20 min post injection. The elimination of the labelled substance was found to follow the pattern of a single exponential function. The following volumes of synovia were determined (mean ± s) : hock, 39.8 ± 2.1 ml; radio-carpal, 12.6 ±1.5 ml; intercarpal, 14.9 ± 0.6 ml; foreleg fetlock joint, 12.5 ± 1.0 ml.     

The Arterial Supply of the Metacarpophalangeal Joint in the Bactrian Camel (Camelus bactrianus)

The arterial supply of the six metacarpophalangeal joints was studied in Bactrian camels. The arterial branches supplying the metacarpophalangeal joints were derived from the metacarpal distal perforating, medial and lateral branches of the palmar metacarpal artery III, medial and lateral branches of the palmar common digital artery III and the abaxial palmar proper digital arteries III and IV. These arterial branches were the proximal dorsoaxial distal metacarpal, distal dorsoaxial distal metacarpal, abaxial distal metacarpal, palmar distal metacarpal, interosseous distal metacarpal, dorsoaxial proximal proximal phalangeal, palmoaxial proximal proximal phalangeal, palmoabaxial proximal proximal phalangeal and dorsoabaxial proximal proximal phalangeal branches. They linked with each other around the metacarpophalangeal joint.     

Sacroiliac Joint of the Horse 3. Histological appearance

To establish a baseline for the histological appearance of the sacroiliac joint of the horse, joint specimens were collected from 41 horses from late fetal life to the age of 14 years. Sagittal sections from the joints were radiographed and sectioned for histological examination.
There was a striking difference in structure between the sacral and iliac articular cartilages, the former being hyaline and the latter predominantly fibrous. Degenerative changes were seen even in young horses and were more markec on the iliac side. The degeneration of the articular cartilage showed a progressive, age-related pattern.     

Sacroiliac Joint of the Horse 1. Gross morphology

A total of 22 morphological features were described in the sacroiliac joints of 41 horses which had no history of any low back condition. Some dramatic differences in both sacral and iliac aspects of joint shape and articular surfaces were seen according to age. These findings were thought to be due to progressive cartilaginous degeneration. Only minor significant differences were seen between left and right sacroiliac joints or between breeds and sex. The iliac surface was more prone to degenerative change. Ankylosis of the joints was not recorded and the incidence of articular or para-articular spur formation was low.     

Sacroiliac Joint of the Horse 2. Morphometric features

The sacroiliac joints were collected from 41 horses from late fetal life to 14 years of age. The sacral and iliac articular surfaces were analysed by morphometry with regard to area, length, width and form factor. The body weights of the animals varied from 10 to 550 kg and the sacral articular surface area from 1.0 to 17.8 cm². Highly significant correlations were found between articular surface dimensions and body weights. Accordingly, the relative size of the joints decreased with increasing body weight/age. The sacral and iliac measurements were essentially comparable. No consistent left-right sidedness was found and no significant sex or breed differences were present.     

Treatment of Exuberant Granulation Tissue in the Horse Evaluation of Four Methods

Four methods of treating granulating wounds on the dorsal aspect of the metacar-pophalangeal and metatarsophalangeal joints of ponies were evaluated. The following treatments were used: Group 1—excision of the granulation tissue with no further treatment; Group 2—cryosurgery; Group 3—excision of the granulation tissue and pressure bandage; and Group 4—excision of the granulation tissue and immobilization of the limb with a plaster cast. The wounds in Group 1 healed fastest, without producing exuberant granulation tissue and with only moderate scar fibrosis. The wounds in Group 2 healed without producing exuberant granulation tissue but with marked scarring. Wounds in Groups 3 and 4 took longer (p < 0.001) to heal compared to wounds in Groups 1 and 2. Wounds in Groups 3 and 4 produced exuberant granulation tissue, but the resultant scars were the least fibrotic.     

Treatment of Degenerative Joint Disease of the Horse: A Review and Commentary

Some of the predisposing factors for the development of degenerative joint disease, such as fatigue, early training, conformation defects, and others, are outlined. Swimming, a controlled weight-bearing exercise, is discussed and strongly recommended for treatment of degenerative joint disease in the horse. A brief review of counterirritants and vesicants, as well as current therapeutic suggestions, are presented. Cryotherapy, which is a relatively new form of counterirritation, is discussed. The benefits and limitations of radiation therapy are briefly discussed, and gamma rays are felt to be superior to x-rays. The most frequently used antiinflammatory drugs are discussed, and the two main categories, corticosteroids and nonsteroidal antiinflammatory drugs, are presented in detail. Among the nonsteroidal antiinflammatory drugs, hyaluronic acid, DMSO, and superoxide dismutase are presented and their mode of action, as well as benefits and disadvantages, are evaluated. Joint lavage is an effective tool in the management of joint disease, because it removes degenerative debris and inflammatory cells from the joint. The management of degenerative joint disease generally involves more than one of the therapeutic regimens mentioned. On the other hand, there is not a single treatment combination that is superior in all situations. The clinician treating degenerative joint disease must select the treatment regimen that works best for him and for the case to be treated. Such a choice must be based on a thorough understanding of applicable therapeutic agents and modes of physical therapy.