Correction of complex three-dimensional deformities at the proximal femur using indirect reduction with angle blade plate and patient-specific instruments: a technical note

Background Corrective osteotomies for complex proximal femoral deformities can be challenging; wherefore, subsidies in preoperative planning and during surgical procedures are considered helpful. Three-dimensional (3D) planning and patient-specific instruments (PSI) are already established in different orthopedic procedures. This study gives an overview on this technique at the proximal femur and proposes a new indirect reduction technique using an angle blade plate. Methods Using computed tomography (CT) data, 3D models are generated serving for the preoperative 3D planning. Different guides are used for registration of the planning to the intraoperative situation and to perform the desired osteotomies with the following reduction task. A new valuable tool to perform the correction is the use of a combined osteotomy and implant-positioning guide, with indirect deformity reduction over an angle blade plate. Results An overview of the advantages of 3D planning and the use of PSI in complex corrective osteotomies at the proximal femur is provided. Furthermore, a new technique with indirect deformity reduction over an angle blade plate is introduced. Conclusion Using 3D planning and PSI for complex corrective osteotomies at the proximal femur can be a useful tool in understanding the individual deformity and performing the aimed deformity reduction. The indirect reduction over the implant is a simple and valuable tool in achieving the desired correction, and concurrently, surgical exposure can be limited to a subvastus approach.

Outcome of Midvastus versus Subvastus Approach in Single Stage Bilateral Total Knee Arthroplasty

Objective: To compare midvastus and subvastus approach regarding operative parameters(lateral retinacular release, operative time, neurovascular injury) and outcome (Knee Society Score, Straight Leg Raise) at 12 weeks in single stage bilateral total knee arthroplasty. Study Design: Randomized clinical trial study Place and Duration of Study: Institute of Orthopaedic Surgery and South City Hospital Karachi from 1st January 2016 to 31st December 2018. Methodology: Fifty two patients of both genders ofmore than 50 years with osteoarthritis grade III or IV and bony changes confirmed by AP and lateral radiographs of knee were included. Patients with previous knee surgeries including high tibial osteotomy, deformities >20°(on mechanical axis), any neuromuscular problem and BMI ≥30 were excluded. Final assessment was done at 12 weeks. Isometric quadriceps strength was assessed by holding of contraction in seconds during the lifting (10cm above the plinth) phase of SLR (patient lying supine).Knee score (preoperative and final follow-up) was performed by Knee Society Score. Results: Thirty five were females and 21 males with mean age 65.3 years (50-78 years). Mean body mass index was 27.8 Kg/m2 (26.4-29.9). In midvastus TKR, the mean operative time was 61.7 minutes (range 52-70) whereas the same was 68.3 minutes (range 58-74) in subvastus TKR with p value 0.002. Rate of lateral retinacular release (LLR) was significantly (p=0.011) different between the midvastus TKR 5 (8.9%) and subvastus TKR 11 (19.6%). Neither group had neurovascular injury or early infection of the knee. Active SLR in subvastus group was achieved in shorter time (mean 3.1 days) as compared to midvastus group (mean 4.7 days). There was no difference (p=0.173) in isometric quadriceps strength at 12 weeks between subvastus TKR (mean 18 seconds) and midvastus TKR (mean 17 seconds). Knee society pain and functional scores were comparable between the two approaches at final follow up. Conclusion: Subvastus exposure has advantage of achieving active straight leg raise earlier while midvastus has lower frequency of lateral retinacular release. No difference in hospital stay and postoperative pain scores. Both subvastus and midvastus approaches are safe and offer comparable Knee Society Score outcomes. Keywords: Midvastus, Subvastus, Total knee arthroplasty, Knee Society Score, Straight leg raise

Correction to: Better outcomes after mini‑subvastus approach for primary total knee arthroplasty: a Bayesian network meta‑analysis

A correction to this paper has been published: https://doi.org/10.1007/s00590-021-03026-9

FACTORS AFFECTING EXPOSURE IN TOTAL KNEE REPLACEMENT USING SUBVASTUS APPROACH

INTRODUCTION: A key factor in minimally invasive knee surgery is protecting and preserving muscles. The muscles provide strength and control of our knee range of motion. The muscles are also an important factor in regaining motion. As one would expect, not cutting or detaching muscles around the knee results in less pain, better motion and faster recovery as in Subvastus approach of TKR. This study is Randomized prospective observational study, in which few signicant patient factor like :- FFD, BMI, Insall-Salvati score, muscle to bone ratio and varus valgus deformity got studied with respect to the Exposure level achieved by surgeon during knee replacement operation via Subvastus approach. This study in near future would help surgeons to decide whether a particular patient for knee replacement can be considered for surgery via Subvastus approach ,which is superior in terms of postop – rehabilitation and pain score than conventional approaches. 60 MATERIALS AND METHODS: patients with difculty in walking or pain in knee, requiring replacement are taken in this study from January 2019 to December 2019. DISCUSSION: The study shows that the exposure level for the surgeons gets restricted when the patient is Obese, muscularand one having xed exion deformity of his knee. Recurvatum on the other hand positively related to exposure level , which means patient with knee recurvatum had better exposure level in Tkr via Subvastus approach. Subvastus approach for Total knee re CONCLUSION: placement has benets of early postop recovery and better patient compliance but greater surgical skills of operating surgeon required because of reduced exposure level in surgery and muscle bulk is preserved.

SMOC Approach for Total Knee Arthroplasty in Valgus Knees

Purpose The subvastus approach sometimes can not provide adequate exposure and lateral approach has disadvantages of closure of the soft tissues and patellar tracking. The hypothesis of this study was that SMOC approach could be used in valgus knees and would offer good function.Methods We retrospectively reviewed 25 patients (25 knees) with valgus deoformity undergoing primary total knee arthroplasty (TKA) with SMOC approach. Necessary soft tissue releases, Visual Analog Scale (VAS), straight leg raising (SLR), International Knee Society score (KSS), radiological alignment were assessed with average follow-up of 16 months.Results KSS improved significantly from 38.5 to 90.3. The mean range of motion increased from 89.5°to 121.8°.The mean tibiofemoral valgus was corrected from preoperative 17.1° to 6.3°. No instability, recurrent valgus deformity, or radiographic loosening was found during follow-up.Conclusions SMOC approach provides adequate exposure and excellent early recovery for TKA in valgus knees, without increase in incidence of complications.