Anterior cruciate ligament (ACL)-retaining total knee arthroplasty (TKA) has been associated with more physiologic motion patterns, more normal knee kinematics, and higher patient preference than ACL-sacrificing implant designs. However, it remains unclear how many osteoarthritic patients can be expected to have an intact ACL at the time of surgery in order to undergo ACL-retaining TKA. A systematic literature review was performed in November 2018 using the PubMed and EMBASE databases. Papers written in English, with more than 10 adult patients relevant to the research question were included, whereas cadaveric, revision, animal and simulation studies and conference abstracts were excluded. Data on ACL retention during intraoperative assessment or MRI scans were extracted and analysed using proportional meta-analyses. Twenty-six eligible publications (4167 knees) were included: 20 using intraoperative assessment, 4 using MRI, and 2 using both. Intraoperative assessment of the ACL during TKA showed that the ligament was present in 78% (95% confidence interval [CI]: 72–84%) and intact in 55% (95% CI: 45–65%) of the patients examined. MRI scans revealed higher percentages of ACL presence and intactness than intraoperative assessment, with 91% (95% CI: 79–96%) of the ACL being present and 68% (95% CI: 28–92%) intact. Fewer studies reported on MRI results compared to studies reporting on the intraoperative status of the ACL. In conclusion, intraoperative assessment suggests that over half of the osteoarthritic patients have an intact ACL at the time of TKA surgery, some of whom may qualify for bicruciate-retaining arthroplasty.

For any figures or tables, please contact authors directly.

TKA (Total Knee Arthroplasty) is a successful operation. Soft tissue problems with TKA are difficult to treat. Flap surgery is successful in treating this problem and salvaging the prostheses. We present results of flap surgery for complicated TKAs over a ten year period, performed by a single surgeon.

Between 1996 and 2005, 31 patients (32 knees) underwent flap surgeries for TKAs. Four of these procedures were done prophylactically in patients with previous knee surgeries. Gastrocnemius, medial fasciocutaneous and anterior compartment flaps were used either solely or in combination based on the size of the defect. The data was collected retrospectively from case-notes and correspondence from the treating orthopaedic surgeons. All the knees included in the study had a minimum follow up of 6 months.

The patients were aged between 50 and 94 years. Indication for primary TKA was osteoarthritis in 26 patients and rheumatoid arthritis in 5. The index orthopaedic surgery was a primary knee arthroplasty in 14 and revision in 13. The average duration between the TKA and flap surgery was 11 weeks (range 1 – 52). Gastrocnemius was the most commonly used local flap (17 cases). Anterior compartment flap was used in 5 cases and in the rest combination of flaps was used. Coagulase -ve Staph. aureus was the most commonly isolated organism from the perioperative wound swabs. Successful soft tissue cover was achieved in 29 of 32 knees (92%). Overall, TKA was salvaged in 23 of 32 knees (72%) and 3 knees (9.7%) underwent arthrodesis. Three (9.7%) patients had above knee amputation, two of these had post op MRSA infection. We could not use a functional knee scoring system due to inadequate information available.

We conclude local flap surgery is a viable and successful procedure for providing soft tissue cover for complicated TKAs with good results.

Purpose: Bone grafting of subchondral voids during ORIF of tibial plateau fractures is commonly performed. The efficacy of various graft materials to resist post-operative articular displacement and stimulate bone regeneration in the grafted zone, remains largely unstudied. Studies in animals with a new composite material have shown that this composite material leads to greater bone formation and stronger bone versus autograft at 13 and 26 weeks. This study was designed to determine whether this material helps resist articular fragment displacement and leads to stronger bone regeneration and better functional outcome in the treatment of tibial plateau fractures.

Methods: Thirty four patients with unilateral tibial plateau fractures (OTA 41A-B), were enrolled in a prospective multicenter single cohort study. The treatment protocol included ORIF and defect augmentation with a composite bone graft substitute (PRODENSE®, Wright Medical Technology). Reduction and bone formation was evaluated and followed with both plain radiographs and CT scans obtained immediately postop and at 12 and 24 weeks. Functional outcome was assessed using the SMFA scores. CT analysis was performed by an independent musculoskeletal radiologist who quantified maintenance of reduction of the articular surface and bone density within the grafted area.

Results: Eighteen of the 34 enrolled patients were eligible for follow-up at 24 weeks (sixteen were not yet eligible for the 24 week time point). Mean change in articular reduction was 0.75mm, Density measures in the region of the initial subchondral void decreased from a mean of 1400 Hounsfield units at baseline (immediately post-op) to 600 at 24 weeks, suggesting bone regeneration and normal remodeling. Short form Musculoskeletal Function Assessment activity scores improved from 55.15 (SD=42.8) at baseline to 20.92 (SD=18.09) at 24 weeks. Complications include 1 DVT, 3 infections and 1 cellulitis, all of which resolved. There was an additional infection that required revision of the ORIF.

Conclusions and Significance: Serial CT evaluations revealed maintenance of post-operative reduction with displacement of less than 1mm. Bone density, in the region of the grafted area was near normal and confirms that the composite graft material promotes strong bone regeneration. Functional outcomes improved with time from surgery and approached that of uninjured cohorts.

Introduction and aims: Soft tissue defects after total knee arthroplasty (TKA) are difficult problems to treat. Flap surgery has been successful in salvaging the prostheses. We present results of flap surgery for exposed TKAs over a 10 year period performed by single surgeon.

Material and Methods: Between 1996 and 2005, 31 patients (32 knees) underwent flap surgeries for TKAs. Four of these procedures were done prophylactically in patients with previous knee surgeries. Gastrocnemius, medial fasciocutaneous and anterior compartment flaps were used either solely or in combination based on the size of the defect. The data was collected retrospectively from case-notes and correspondence from the treating orthopaedic surgeons.

Results: The patients were aged between 50 and 94 years. Indication for primary TKA was osteoarthritis in 25 patients and rheumatoid arthritis in 5. Coagulase negative Staph. aureus was the most commonly isolated organism. In patients using steroids, 4 of 6 (71.4%) knees had good or satisfactory outcome compared to 22 of 24 (91.7%) knees in patients not on steroids. Smoking did not influence the outcome of flap surgery . The average duration between the TKA and flap surgery was 11 weeks (range 1 – 52). Successful soft tissue cover was achieved in 30 of 32 knees (94%). Overall, TKA was salvaged in 20 of 28 knees (71.4%) knees, 3 knees (9.7%) underwent arthrodesis and above knee amputation was performed in 4 (12.4%). The information gathered from case notes and orthopaedic surgeons was insufficient to use a knee score for evaluating the functional outcome of the procedure.

Conclusion: Local flap surgery for providing soft tissue cover for exposed TKA is a viable and successful procedure with good results.