A cranial intercondylar arthroscopic approach to the caudal medial femorotibial joint of the horse

Reason for performing study: Current noninvasive techniques for imaging the soft tissue structures of the stifle have limitations. Arthroscopy is commonly used for the investigation and treatment of stifle pain. Cranial and caudal arthroscopic approaches to the femorotibial joints are used. However, complete examination of the axial aspect of the medial femorotibial joint (MFTJ) is not possible currently. Objective: To develop a cranial approach to the caudal pouch of the MFTJ and to assess whether it would allow a more complete examination of the compartment and facilitate the caudomedial approach. Method: The regional anatomy was reviewed and the technique developed on cadavers. A series of nonrecovery surgeries were performed to evaluate the procedure, which was then used in 7 clinical cases. Advantages compared to existing techniques and complications encountered were recorded. Results: Successful entry into the caudal pouch of the MFTJ was achieved in 20 of 22 cadaver legs, 8 of 8 joints of nonrecovery surgery horses and 6 of 7 clinical cases operated. The caudal ligament of the medial meniscus could be visualised, along with other axial structures of the caudal joint pouch. The technique was used to facilitate a caudomedial approach and allowed better triangulation within the joint space. Complications were minor and included puncture of the caudal joint capsule and scoring of the axial medial femoral condyle. Conclusions and potential relevance: It is possible to access the caudal pouch of the MFTJ arthroscopically using a cranial intercondylar approach. The technique has advantages when compared to existing techniques and is associated with few significant complications. A cranial approach to the caudal pouch of the MFTJ could complement existing techniques and be useful clinically.     

Concurrent or sequential development of medial meniscal and subchondral cystic lesions within the medial femorotibial joint in horses (1996–2006)

Reasons for performing study: Medial meniscal injuries and subchondral cystic lesions (SCL) are known to occur independently within the medial femorotibial (MFT) joint in horses. However, there are no reports of a potential clinical relationship between these 2 types of lesions. Objectives: To: 1) document the concurrent presence or sequential development of medial meniscal and SCL of the medial femoral condyle within the MFT joint; and 2) determine the prognosis with both types of lesions. Methods: Retrospective case series of horses with both a medial meniscal and SCL of the medial femoral condyle identified concurrently or sequentially by radiography, arthroscopy or post mortem examination. Case records and radiographs were reviewed, and a telephone survey of referring veterinarians, owners and trainers was conducted. Results: Twenty‐one horses (9.1% of all horses undergoing MFT joint arthroscopy) were identified to have both a medial meniscal injury and SCL of the medial femoral condyle. Thirteen horses had both abnormalities identified concurrently, 6 developed a meniscal lesion subsequent to SCL debridement, and 2 developed a SCL subsequent to a medial meniscal injury. Only 4/19 horses were classified as successful and returned to their intended use. The severity of the meniscal injury was significantly associated with the severity of lameness but not with outcome. Conclusions: A low percentage of horses may develop both a meniscal injury and SCL of the medial femoral condyle within the MFT joint and have a poor prognosis. Potential relevance: Trauma to the MFT joint may lead to both meniscal and subchondral bone damage of the medial femoral condyle that may be recognised concurrently or sequentially.     

Arthroscopic treatment of fractures of the lateral malleolus of the tibia: 26 cases

Reasons for performing the study: A minimally invasive arthroscopic technique for removal of fractures of the lateral malleolus of the tibia is considered to be beneficial but data to this effect are required. Hypothesis: Arthroscopic removal of fractures of the lateral malleolus of the tibia is technically feasible, provides a comprehensive evaluation of the tarsocrural joint and enables removal of remote comminuted fragments and disrupted short collateral ligaments. The technique is associated with low patient morbidity, requires only short periods of hospitalisation and affords a good prognosis to affected horses. Methods: The case records of all horses that underwent arthroscopic removal of a fractured lateral malleolus of the tibia, admitted to a referral hospital, were evaluated retrospectively. Follow‐up information was obtained from race records and by telephone questionnaire. Results: Fractures were successfully removed arthroscopically in all cases following dissection from the short lateral collateral ligaments. Significant post operative complications occurred in only one horse. All other horses recovered well from surgery and of 22 horses with long‐term follow‐up, 18 returned to their previous use. Conclusion: Arthroscopic removal of fractures of the lateral malleolus of the tibia is technically demanding, but can be performed with minimal complications and with low patient morbidity and short periods of hospitalisation. The majority of horses are able to successfully return to work following the procedure. Potential relevance: The advantages of arthroscopic removal compared to removal via arthrotomy make this the technique of choice for treatment of fractures of the lateral malleolus of the tibia.     

Arthroscopically‐assisted removal of an osteochondral fragment from the equine elbow using a caudo‐medial approach

An 8‐year‐old Polo pony mare was admitted for investigation of lameness related to swelling of the elbow. An intra‐articular fragment from the proximo‐medial radius was identified on radiographic examination. The fragment was removed arthroscopically under general anaesthesia via a caudo‐medial approach to the elbow joint.     

Arthroscopic removal of fractures of the lateral malleolus of the tibia in the tarsocrural joint: A retrospective study of 13 cases

There is limited information on the treatment of lateral malleolus (LM) fractures in the horse, with no previously published case series for the outcome following arthroscopic removal of such fractures. This report reviews and evaluates findings of a retrospective study of 13 horses admitted to a private equine referral hospital over a 10 year period (1999–2009) that underwent arthroscopic removal of fractures of the LM. Hospital records were reviewed and details including patient history, aetiology of the fracture and limb affected, results of all diagnostic tests and surgical reports were documented. Performance information concerning Thoroughbred horses that went onto race post operatively was collected using an online database. Owners and trainers were contacted regarding the return to performance for non‐Thoroughbred cases or those that did not go onto race post operatively. Of the 13 horses presented, 12 were Thoroughbreds, 9 of which were National Hunt racehorses and 3 were Flat racehorses. The other horse in the study was used for general purpose riding. All cases presented with an acute unilateral fracture. Eleven of the 13 had >6 months post operative follow‐up and all were nonlame. Of the 12 Thoroughbreds, 10 have raced again, a total of 104 times (median 5 times). The median time from surgery to return to racing was 241 days (180–366 days). It is concluded that horses with fractures of the LM have an excellent prognosis for return to full athletic performance following arthroscopic debridement; and that arthroscopic fragment removal is an appropriate treatment method for fractures of the LM.     

Surgical repair of fractures of the lateral and medial tibial malleoli in a yearling Arabian filly

A yearling Arabian filly presented with a history of acute hindlimb lameness, marked tarsocrural effusion and associated soft tissue swelling and was diagnosed with fractures of both the lateral and medial malleoli of the distal aspect of the tibia. The fractures were repaired using a combination of cortical bone screws placed in lag fashion and a tension band wire. A full limb cast bandage was placed for recovery from general anaesthesia and the early post operative period. Despite radiographic development of osteoarthritis, 21 months after surgery the filly was clinically sound and racing successfully.     

Gas arthroscopy for removal of osteochondral fragments of the palmar/plantar aspect of the metacarpo/metatarsophalangeal joint in horses

Objective— To evaluate the use of carbon dioxide (CO₂) gas for joint distention during arthroscopy for removal of osteochondral (OC) fragments of the palmar/plantar aspect of the metacarpo (MCP)/metatarsophalangeal (MTP) joints in horses.
Study Design— Clinical study.
Animals— Horses (26) with OC fragment(s) of palmar/plantar aspect of 1 or 2 MCP/MTP joint(s).
Methods— OC fragments were removed using arthroscopic technique. Joint distention was maintained by isotonic Ringer's acetate at the beginning and at the end of the procedure but during fragment removal, CO₂ was used for joint distention. After surgery, fragment removal was confirmed by radiography. Horses were discharged the day after surgery, and outcome was determined by telephone contact 3–24 months later.
Results— CO₂ joint distention resulted in a sharp image without villi obscuring the operative field. Fragments were identified and completely removed in all horses except one where a 1 mm × 3 mm radiodense body was seen on postoperative radiographs. In 5 horses, bleeding from the arthroscopic or instrument portal precluded optimal visualization when the joint was distended by gas; however, repeatedly rinsing the tip of the arthroscope with Ringer's acetate solution delivered from the fluid ingress line easily restored joint visualization. No specific complications were observed postoperatively.
Conclusions— Joint distention by CO₂ permitted optimal visualization of the palmar/plantar aspect of the MCP/MTP joints, which facilitated fragment removal.
Clinical Relevance— Gas arthroscopy is a useful technique for removal of OC fragments of the palmar/plantar aspect of the MCP/MTP joints in horses.     

Computed tomographic diagnosis of incomplete palmar cortical (fatigue) fracture of the third metacarpal bone in two young adult endurance horses

Two young adult endurance horses were presented for investigation of sudden-onset forelimb lameness during competition. Clinical examination revealed a severe forelimb lameness and pain on palpation of the proximal palmar metacarpal area. Initial radiographic survey of the affected forelimb was unremarkable in both cases. A week of box rest resulted in only a mild improvement in the lameness. A second radiographic examination did not reveal any significant abnormalities. In both cases, scintigraphic examination was suggested, but was declined by the owner, and the lameness had significantly improved after local infiltration of 3 mL of anaesthetic solution in the proximal suspensory region. Radiographic and ultrasonographic examinations of the carpus and proximal suspensory region were unremarkable in Case 2. Case 1 had increased thickness of the medial lobe of the proximal aspect of the suspensory ligament. A computed tomographic examination was performed and an incomplete longitudinal (fatigue) fracture of the proximal third metacarpal bone was detected. After 8 months of box rest and rehabilitation, re-examination revealed resolution of the lameness in both cases. Advanced diagnostic imaging should be considered in young endurance horses with severe lameness during competition or training, in which radiographic and ultrasonographic examinations are unremarkable or do not explain the severity of the lameness. Computed tomography imaging is considered a useful diagnostic imaging technique to detect incomplete longitudinal palmar metacarpal cortical (fatigue) fractures due to its ability to provide excellent bone detail.     

Coronoidectomy as a treatment for mandibular immobility caused by fracture of the coronoid process in three horses

This report describes the history, clinical signs and treatment of three horses suffering from deviation and immobility of the mandible resulting from fracture of a coronoid process of the mandible. Deviation and immobility resulted from impingement of a callus between the temporal bone and zygomatic arch. Fracture of the coronoid process was identified by using radiography, ultrasonography, computed tomography or a combination of two or more of these imaging modalities. Osteoarthritis of the ipsilateral temporomandibular joint of two horses was identified. All horses were treated by excising the fractured coronoid process, and two were also treated by excising the diseased ipsilateral mandibular condyle. All horses were able to open their mouth more widely immediately after surgery. One horse experienced moderate post-operative haemorrhage, and all had severe shear mouth. Shear mouth was ameliorated gradually over many months by rasping dental overgrowths. Mandibular movement of all horses improved, allowing efficient mastication of feed. One horse was able to be used as a showjumper, one horse was sold at Thoroughbred yearling sales and was lost to follow-up, and one horse died from an unrelated gastrointestinal disease 10 months after mandibular coronoidectomy and condylectomy.     

Palmar or plantar process fractures of the distal phalanx in riding horses: 22 cases (1994–2003)

No case series exists in the literature describing palmar/plantar process fractures (PPFs) of the distal phalanx in a nonracehorse population. We aim to describe the distribution of these injuries, together with their clinical, radiographic and scintigraphic features. In a retrospective case study, horses were selected based on radiographic evidence of a PPF. Data were collected relating to clinical and lameness examination, radiography, scintigraphy, management and follow‐up information. Oblique and flexed oblique radiographic views of the distal phalanx are the most sensitive in detecting PPFs of the distal phalanx and this study concluded that fractures of palmar or plantar process are likely to be missed in horses showing mild lameness if oblique radiographic views of the palmar process are not included.     

Serum levels of the immunoglobulins IgG and IgG(T) in horses

Levels of the immunoglobulins IgG and IgG(T) in serum in Norwegian horses of the breeds “Døle” and “Fjord” were determined by the quantitative radial immunodiffusion test.No significant differences were apparent between the 2 Norwegian breeds. The immunoglobulin levels were approximately in the same range as previously reported for Shetland ponies.Immunoglobulins could not be detected in the newborn foal. As early as 24 hrs. after birth the mean immunoglobulin level was within the adult range. After a drop during the first month of life, the immunoglobulins increased. IgG(T) rose more rapidly and to a higher level than IgG.In 2 year old horses, IgG(T) was significantly higher than in adults, while IgG was significantly lower. IgG(T) seems to be a very important immunoglobulin in foals and young horses.