Partial Cranial Cruciate Ligament Tears Treated with Stem Cell and Platelet-Rich Plasma Combination Therapy in 36 Dogs: A Retrospective Study

Objective: To evaluate outcomes in 36 dogs with a partial cranial cruciate ligament (CCL) tear treated with autologous bone marrow aspirate concentrate (BMAC) or adipose-derived progenitor cells (ADPC) with platelet rich plasma (PRP) combination. Materials and methods: Medical records of client-owned dogs diagnosed with an early partial (<= 50%) tear of the craniomedial band of the CCL that was treated with BMAC PRP or ADPC PRP were reviewed from 2010 to 2015. Signalment, medical history, physical and orthopedic examination, objective temporospatial gait analyses, radiographs, day 0 and day 90 diagnostic arthroscopy findings, treatment, and outcome were among the data collected. A functional owner questionnaire, including the validated Helsinki chronic pain index (HOPI), was sent to owners whose dog was known to not have had a tibial plateau leveling osteotomy (TPLO). Statistical analysis was performed on data, where significance was established at p < 0.05. Results: Stifle arthroscopy findings at 90 days posttreatment were available on 13 of the 36 dogs. In nine dogs, a fully intact CCL with marked neovascularization and a normal fiber pattern was found with all previous regions of disruption healed. One dog revealed significant improvement and received an additional injection. The remaining three dogs had a >50% CCL tear, and a TPLO was performed. Four additional dogs were known to have had a TPLO performed elsewhere. Baseline and day 90 posttreatment objective gait analyses were available on 11 of the 36 dogs. A significant difference was found between the treated limb total pressure index percent (TPI%) at day 0 and day 90 (p = 0.0124), and between the treated limb and contralateral limb TPI% at day 0 (p = 0.0003). No significant difference was found between the treated limb and contralateral limb TPI% at day 90 (o = 0.7466). Twelve questionnaires were returned, of which eight were performance/sporting dogs. Seven of the eight had returned to sport; the remaining dog had just begun a return to sport conditioning program 6 months posttreatment. All 12 respondents believed that their dog had an excellent or very good quality of life and rated their dog's procedural outcome as excellent or good. Conclusion: The use of BMAC-PRP and ADPC-PRP shows promise for the treatment of early partial CCL tears in dogs. Further studies are needed and should be randomized, blinded, and controlled.