Bayer Karol, Winkels Philipp, Andreoni Angelo Alessandro, Schmierer Philipp, Rohwedder Thomas, Pozzi Antonio, Böttcher Peter
Small Animal Clinic, Free University of Berlin, Berlin, Germany.
Vetacare, Erftstadt, Germany.
Open Vet J. 2019 Oct;9(3):205-215. doi: 10.4314/ovj.v9i3.4. Epub 2019 Aug 1.
Medial coronoid process disease is the most common manifestation of canine developmental elbow disease which can progress to a more severe medial compartment disease (MCompD) characterized by full-thickness cartilage loss of the medial coronoid process and the medial humeral condyle. Among others, the "Canine Unicompartmental Elbow" (CUE) has been reported to be an effective treatment strategy for MCompD, with full in 47.6% and acceptable function in 43.7% at 6 months or later of follow-up.
To report on our clinical experiences with the CUE system using the caudo-medial approach in terms of both complications and functional outcome.
Medical records of dogs that underwent CUE procedure using a caudo-medial approach over a 3-year period were retrospectively reviewed. This covered epidemiological data, bi-planar radiographs, subjective gait analysis, owner questionnaire, surgical reports, as well as second-look arthroscopic findings when available.
In total, 52 CUE procedures were performed in 44 dogs with a median age of 8.0 years (IQ: 5.0-10.0) and a median bodyweight of 31.9 kg (ranging 20-48 kg) at the surgery. Four cases never return for follow-up, but were included in the analysis to increase the number of cases with pre- and intra-operative data. Mean follow-up time available for the remaining 48 cases was 7.1 (SD: 5.2) months. Radiographic derived implant positioning and alignment proved to be satisfactory in the sagittal plane but parallelism in the frontal plane was only present in three cases. Second-look arthroscopy in five cases with delayed or disappointing functional improvement showed evidence of implant-related contact lesions and progressive erosion of the medial coronoid area in three elbows. Overall, complications occurred in 11 cases (21%), being major in eight (15%) and minor in three (6%). Major complications included refractory pain and lameness 6 to 12 months postoperatively in five cases. At last follow-up, 12 cases (25%) were considered to have full function, 35 cases (73%) acceptable function, and in one case, the function was considered unacceptable. As the only variable related to functional outcome, age had a negative predictive value for full function.
The CUE procedure appears to be an effective treatment option for patients with MCompD. Older dogs might be at risk of having an inferior clinical outcome when compared to young patients. The reason for this is unknown and will have to be evaluated in future studies. Compared to a CUE case series of 103 elbows operated through a medial approach, using a caudo-medial approach decreased the incidence of approach-related complication. Nevertheless, the functional outcome in the current case series was less favorable than previously reported. These conflicting findings as well as the occurrence of potentially implant mechanical conflict at the medial joint compartment despite CUE warrants further studies.
内侧冠状突疾病是犬类发育性肘关节疾病最常见的表现形式，可发展为更严重的内侧关节疾病（MCompD），其特征是内侧冠状突和肱骨内侧髁的全层软骨缺失。其中，“犬单关节肘关节”（CUE）已被报道为治疗MCompD的一种有效策略，在随访6个月或更晚时，47.6%的犬完全恢复，43.7%的犬功能可接受。
报告我们使用后内侧入路的CUE系统在并发症和功能结果方面的临床经验。
回顾性分析在3年期间采用后内侧入路进行CUE手术的犬的病历。这包括流行病学数据、双平面X线片、主观步态分析、主人问卷、手术报告，以及如有可用的二次关节镜检查结果。
总共对44只犬进行了52次CUE手术，手术时犬的中位年龄为8.0岁（四分位间距：5.0 - 10.0），中位体重为31.9 kg（范围20 - 48 kg）。4例未返回进行随访，但纳入分析以增加有术前和术中数据的病例数量。其余48例的平均随访时间为7.1（标准差：5.2）个月。X线片显示植入物在矢状面的定位和对线令人满意，但仅3例在额状面平行。对5例功能改善延迟或不理想的犬进行二次关节镜检查，发现3个肘关节有与植入物相关的接触性病变和内侧冠状突区域的进行性侵蚀。总体而言，11例（21%）发生并发症，其中8例（15%）为严重并发症，3例（6%）为轻微并发症。主要并发症包括5例在术后6至12个月出现难治性疼痛和跛行。在最后一次随访时，12例（25%）被认为功能完全恢复，35例（73%）功能可接受，1例功能不可接受。作为与功能结果相关的唯一变量，年龄对完全恢复功能具有负预测价值。
CUE手术似乎是MCompD患者的一种有效治疗选择。与年轻患者相比，老年犬可能有较差临床结果的风险。其原因尚不清楚，有待未来研究评估。与通过内侧入路进行手术的103个肘关节的CUE病例系列相比，采用后内侧入路降低了与入路相关并发症的发生率。然而，当前病例系列的功能结果不如先前报道的好。这些相互矛盾的发现以及尽管采用CUE但在内侧关节腔仍发生潜在植入物机械冲突的情况值得进一步研究。
