Assessing the Role of Minimal Medial Tissue Release during Navigation-Assisted Varus Total Knee Arthroplasty Based on the Degree of Preoperative Varus Deformity

We assessed the impact of a minimal medial soft-tissue release with complete peripheral osteophyte removal on the ability to attain manual preresection deformity correction during navigation-assisted total knee arthroplasty (TKA) for varus osteoarthritis. We included 131 TKAs for 109 patients with medial compartment predominant osteoarthritis. The steps for achieving minimal medial soft-tissue release were performed as follows: (1) elevation of a periosteal sleeve to 5-mm distal to the joint line and (2) complete removal of peripheral osteophytes. The evaluation criteria of this study were as follows: (1) age, (2) height, (3) weight, (4) body mass index (BMI), (5) sex, (6) the preoperative femorotibial mechanical angle in the neutral position before medial release and (7) the mechanical angle in maximum manual valgus stress after the two-step medial-release procedure (measured on the navigation screens). Multiple regression analysis of the criteria was performed to determine the degree of varus deformity that allowed neutral alignment but required extensive medial release. The femorotibial mechanical angle in the neutral position before medial release and sex correlated with the mechanical angle in maximum manual valgus stress on the navigation screen after medial release (r = 0.72, p < 0.001). Based on the regression formula, the maximum degree of preoperative varus deformity that allowed neutral alignment by the minimum medial-release procedure was 5.3 degrees for males and 9.1 degrees for females. The magnitude of deformity which has an impact on the ability to correct varus deformity (by minimal soft-tissue release and complete osteophyte removal) was clarified. If the preoperative degree of varus deformity was within 5.3 degrees for males and 9.1 degrees for females, an extensive medial release was not required to obtain neutral alignment.

Medial abrasion syndrome: a neglected cause of persistent pain after knee arthroplasty

Introduction Persistent post-operative pain (PPOP) has detracted from some otherwise successful knee arthroplasties. This study investigated medial abrasion syndrome (MAS) as a cause of PPOP after knee arthroplasty. The surgical techniques and outcomes of incorporating this concept into the management of both primary arthroplasty cases and patients suffering from unknown causes of PPOP after arthroplasties were presented. Materials and methods In a 1-year period, the author performed unicompartmental or total knee arthroplasty (the UKA or TKA group) that also eliminated medial abrasion phenomenon (MAP) on 196 knees of 150 patients at advanced stages of knee osteoarthritis (OA). During the same year, 16 knees of 16 patients with unknown causes of PPOP after knee arthroplasties were referred to the author for the arthroscopic medial release procedure (the AMR group) after being diagnosed as MAS. Subjective satisfaction, Knee Society Score (KSS), and Knee injury and Osteoarthritis Outcome Score (KOOS) evaluations were used for outcome study. Results All 166 patients were followed for more than 3 years (mean 3.7 years, 3.1–4.2) for the outcome study. All knees receiving arthroplasty showed medial plicae with MAP at the time of surgery. Only 2 of them suffered from PPOP: one was a neglected tibial plateau fracture with residual varus deformity after UKA, and the other was a late infection after TKA and received revision. The satisfactory rate was 98.8% in the UKA group, 99.1% in the TKA group, and 100% in the AMR group. The Knee Society Scores and all subscales of KOOS were statistically improved in all groups. Conclusions MAS is a cause of pain in patients who have received knee arthroplasties, and MAP should be eliminated to ensure a successful knee arthroplasty. PPOP after knee arthroplasty can be caused by MAS, which can be managed by AMR.

Medial Abrasion Syndrome: A Neglected Cause of Persistent Pain After Knee Arthroplasty

Background: Persistent postoperative pain (PPOP) has detracted from some otherwise successful knee arthroplasties. This study investigated medial abrasion syndrome (MAS) as a cause of PPOP after knee arthroplasty and presented the technique and outcome of arthroscopic medial release (AMR) procedure to treat such patients. Methods: In a one-year period, the author performed unicompartmental or total knee arthroplasty (the UKA or TKA group) that also eliminated MAS on 196 knees of 150 patients at advanced stages of knee osteoarthritis (OA). During the same year, 16 knees of 16 patients with unknown causes of PPOP after knee arthroplasty were referred to the author for the AMR procedure (the AMR group). Subjective satisfaction, Knee Society Score (KSS), and Knee injury and Osteoarthritis Outcome Score (KOOS) evaluations were used for outcome study.Results: All 166 patients were followed up for more than 3 years (mean: 3.7 years, 3.1-4.2) for outcome study. All knees receiving arthroplasty showed pathologic medial plicae of various severities at the time of arthroplasty. Only 2 patients suffered PPOP: one was a neglected tibial plateau fracture with residual varus deformity after UKA and the other was a late infection after TKA and received revision. The satisfactory rate was 98.8% in the UKA group, 99.1% in the TKA group, and 100% in the AMR group. The Knee Society scores and all subscales of KOOS were statistically improved in all groups.Conclusion: MAS is a cause of pain in patients who have received knee arthroplasty, and MAS should be managed before wound closure to ensure a successful knee arthroplasty. PPOP after knee arthroplasty can be caused by MAS, which can be managed by AMR.

Primary Results of Medial Epicondylar Osteotomy in Patients with Severe Bilateral Varus Knee Candidate for Total Knee Replacement

Background Total knee arthroplasty is a challenging task in patients with severe varus deformity. In most of these patients, an extensive medial release is needed that may lead to instability. Medial epicondylar osteotomy may be a better substitute for complete medial collateral release. Materials and Methods Fourteen patients with bilateral knee osteoarthritis and severe varus deformity were enrolled in this study. In one side, the patients underwent medial epicondylar osteotomy for mediolateral imbalance if the only option was superficial medial collateral ligament (MCL) release. In contralateral side, the extensive medial release was performed and MCL was released either by pie-crusting technique or by subperiosteally release. The results of the two sides were compared. Patients were followed up for 12 months after the operation. Physical examination, clinical questionnaires, and radiography findings were recorded. Union of the osteotomies fragment and complications was evaluated. Results The mean varus angle before surgery was 21.6 ± 4.7 degrees, which was corrected to 8.6 ± 2.9 degrees after operation with an extensive medial release. The mean varus angle of contralateral side was 22.6 ± 1.7 degrees, which was corrected to 7.5 ± 2.3 degrees following medial femoral epicondyle osteotomy. There was no significant difference in varus correction (p = 0.1). Medial joint line opening in valgus stress test was 2.7 ± 0.4 mm in the osteotomized side and 3.5 ± 0.9 mm in contralateral side. Mean range of motion for the osteotomized side was 97.8 ± 4.3 degrees and 100.7 ± 2.7 degrees for contralateral side (p = 0.6). Nonunion occurred in a case in the osteotomized side and no medial instability was observed in medial release or osteotomies sides. No statistical difference was recorded based on clinical questionnaires (Oxford and WOMAC [Western Ontario and McMaster Universities Osteoarthritis Index] scores). Conclusion Medial epicondylar osteotomy is a safe technique with the well-controlled medial extensive release in the patients with severe varus deformity during total knee arthroplasty.

Complications Following Surgical Correction of Medial Patellar Luxation in Small-to-Medium-Size Dogs

Objective The main aim of this study was to describe complications in dogs weighing < 20 kg treated for medial patellar luxation and to determine risk factors associated with these complications. Materials and Methods Medical records were reviewed and cases were grouped based on four techniques of stabilization for the tibial tuberosity transposition (TTT). Variables including animal signalment, clinical presentation, TTT technique, other concurrent surgical techniques and associated complications were investigated. Multiple logistic regression was used to determine the association of the same variables with specific complications such as tibial tuberosity fractures or avulsions, patellar reluxation and implant-related complications. Results Of the 100 procedures performed, 37 suffered a complication. There were no significant differences in the overall complication rate between TTT stabilization techniques. Preservation of the tibial tuberosity distal cortical attachment was associated with a reduced risk of implant-related complications, whereas adding a medial release to the surgical techniques was associated with an increased risk of medial patellar reluxation. The type of trochleoplasty performed did not affect the complication rate. Conclusions In the current study, a high rate of complications was found in dogs < 20 kg undergoing medial patellar luxation surgery. Performing a medial release and preserving the distal cortical attachment of the tibial tuberosity were the only variables associated respectively with an increase and a reduction in the risk of postsurgical complications.

Effectiveness and Safety of Needle Medial Collateral Ligament Pie-Crusting in Total Knee Arthroplasty: A Cadaveric Study

Medial collateral ligament (MCL) pie-crusting technique in total knee arthroplasty (TKA) is one of the methods of medial release. The effects and risks of blade pie-crusting have been reported in previous studies. However, only a few have reported the safety and efficacy of needle pie-crusting. In this cadaveric study, we quantitatively evaluated the amount of gap change by MCL needle pie-crusting. We investigated five knees of four fresh human cadavers and performed posterior-stabilized TKA. Only deep MCL release as the medial release was conducted. We punctured the MCL from the deep layer to the superficial layer using a 18 G needle in a 90-degree flexion position for 0, 10, 20, 50, 75, and 100 times. Medial and lateral gaps were measured accurately with a balancer at determined times in 0 and 90-degree flexion positions. Changes in medial and lateral gaps were not significant differences in flexion and extension position. However, in 90-degree flexion, medial gap changes were tended to be larger than lateral gap changes. A 0.6 mm additional medial release and a 0.2 mm additional lateral release were found per 10 times pie crust in flexion position (100 times, p: 0.08). However, large differences existed among the cases. Needle pie-crusting is safer than blade pie-crusting because of the small efficacy of one-time pie crust. MCL needle pie-crusting showed varied effects for each case. This result indicates the risk of relaxation of an unexpected gap. Caution should be taken when choosing between needle pie-crusting and blade pie-crusting.