Journal of Experimental Orthopaedics最新文献

Purpose

The learning curve of a single surgeon performing hip arthroscopy is reported to be steep, but, to date, the inflection point after which procedures are more successful is still unknown. The aim of this study was to design a learning curve focused on clinical outcomes, complications and revision/conversion rates.

Methods

Seventy-one hip arthroscopies performed for femoroacetabular impingement (FAI) by a single surgeon, with a minimum follow-up of 5 years, were considered. Demographics, intraarticular findings and operative and traction time were detailed. HOOS score, subjective outcomes, 30-day complication rates, complication rates, revision arthroscopies and conversions to hip arthroplasty were recorded.

Results

The mean follow-up was 7.5 ± 1.8 years (range: 5–11). The progression of the learning curve implied a reduction in surgical time (r: −0.847), traction time (r: −0.806) and postoperative outcomes (r = 0.444). When the procedures were divided into three consecutive groups (25 vs. 25 vs. 21 procedures) or two consecutive groups (36 vs. 35 cases), the first group had a higher occurrence of 30-day complications (p = 0.002 and p = 0.025, respectively) and the last group experienced a significant amelioration in terms of HOOS score between the preoperative and the postoperative condition (p < 0.001 and p = 0.018).

Conclusions

The inflection point of the hip arthroscopy learning curve is between 25/36 procedures. The first arthroscopies were impacted by higher complications and lower clinical results but no higher rates of revision and conversion to arthroplasty.

Level of Evidence

Level IV.

Purpose

Tibial valgus osteotomy has shown to be a successful and cost-effective procedure. The advent of image processing and three-dimensional (3D) printing is an interesting tool for achieving more accurate and reproducible results. The aim of our study was to compare the accuracy of the conventional technique and the use of customized guides in the correction of tibial deformities in tibial varus patients, the surgical and clinical benefits, and the impact of treatment in the outpatient setting.

Methods

A prospective cohort of 30 patients who underwent tibial valgus osteotomy were selected and randomized into two groups (3D-printed guidewires and conventional techniques). All patients underwent a complete radiological study to plan the surgical procedure. During the surgical procedure, the surgical time and X-ray exposure were analysed. The following results were evaluated: surgical time and X-ray exposure, the correlation between the planned correction and the correction obtained at 3 post-operative months, pre- and post-operative knee injury and osteoarthritis outcome score (KOOS) value at 3 and 12 months, and differences between the two groups in terms of the correction obtained.

Results

Radiation exposure in the ‘3D-guide’ group was significantly different (8 [±4.51], p < 0.05), whereas surgical time was not significantly different between the control and guide 3D groups (60.69 [±8.89] and 53.43 [±11.69], respectively). At the 3-month follow-up, the post-operative hip–knee–ankle and post-operative mechanical–proximal–tibial angle were not significantly different (p > 0.05). At 3- and 12-month post-surgery, the Knee Injury and Osteoarthritis Outcome Score (KOOS) did not significantly differ between the conventional technique and the 3D-guide technique (p > 0.05). The KOOS at 3 months were 87.86 (±5.64) for the control group and 88.46 (±3.53) for the 3D-guide group, while at 12 months they were 91.5 (±5.72) for the control group and 88.57 (±8.81) for the 3D-guide group.

Conclusion

Customized 3D-printed guides do not permit better correction or functional results than the conventional technique; rather, they reduce surgical time and intraoperative radiation exposure.

Level of Evidence

II.

Purpose

The purpose of this retrospective study was to evaluate the efficacy of using a lateral wedge insole (LWI) during the first 3 months after medial meniscus posterior root (MMPR) repair.

Methods

Overall, 179 patients were categorized into LWI use (LWI group, 90 patients) and nonuse (control group, 89 patients) groups. Patients in the LWI group were instructed to wear an LWI from the initiation of load bearing up to 3 months postoperatively. Medial meniscus extrusion (MME) was evaluated preoperatively and 1 year postoperatively, Kellgren–Lawrence (KL) grade and clinical scores were evaluated preoperatively and 2 years postoperatively, and second-look arthroscopic meniscal healing scores were evaluated at 1 year postoperatively.

Results

The proportion of patients with KL grade progression at 2 years postoperatively was significantly lower in the LWI group than in the control group (23.3% vs. 39.3%; p = 0.024). Change in the MME at 1 year postoperatively was significantly smaller in the LWI group than in the control group (1.1 ± 1.2 vs. 1.6 ± 1.4 mm; p = 0.042). The Lysholm score (p = 0.003) and Knee Injury and Osteoarthritis Outcome Scores-sport and recreation function (p = 0.027) at 2 years postoperatively were significantly superior in the LWI group than in the control group. The arthroscopic meniscal healing score after 1 year was not significantly different between the LWI and control groups (total score, 7.6 ± 1.1 vs. 7.4 ± 1.3 points; p = 0.732). The anteroposterior width of the repaired posterior root at 1 year second-look evaluation was significantly broader in the LWI group than in the control group (7.7 ± 1.6 vs. 6.9 ± 1.6 mm; p = 0.001).

Conclusions

The use of LWI is an effective way to delay postoperative osteoarthritis progression and improve clinical outcomes after MMPR repair.

Level of Evidence

Level III.

Purpose

Malalignment of the lower extremity can affect one, two or all three anatomic planes. We hypothesized an influence between the malalignment of the coronal and axial planes.

Methods

A total of 356 lower extremities of 226 patients were included. Femoral and tibial torsion were assessed in computer tomographic scans while frontal plane alignment was measured in long-leg standing radiographs. The mechanical angles were for knee phenotyping according to the coronal plane alignment of the knee classification. The correlation between the coronal alignment and torsional profile was analyzed. The population was divided into three groups according to leg alignment (valgus, neutral, varus) and gender.

Results

As the coronal alignment changed from valgus to varus the tibial external torsion increased (r = 0.35; p < 0.001). Femoral internal torsion increased as well but only in the male subgroup (r = −0.34; p < 0.001). Both femoral internal torsion and tibial external torsion increased with higher mechanical lateral distal femoral angle (mLDFA) but were not related to mechanical medial proximal tibial angle. A distinct pattern of results concerning knee phenotypes in relation to femoral and tibial torsion was found.

Conclusion

Tibial torsion correlated with increasing varus alignment while both femoral and tibial torsion correlated with higher mLDFA, but the correlations were weak. Therefore, the coronal alignment does not enable to predict the degree of femoral and tibial torsion. This study demonstrates that an individual approach to each patient with lower limb malalignment is unavoidable.

Level of Evidence

Level III.

Purpose

Micro-fragmented adipose tissue is emerging as a promising option for the treatment of various diseases including knee osteoarthritis (OA), though clinical trials are often limited by short follow-up periods. Our aim was to evaluate the safety and clinical outcomes of an arthroscopic debridement followed by a single injection of micro-fragmented adipose tissue in patients affected by knee OA.

Methods

From 2016 to 2020, patients affected by knee OA were enroled. Micro-fragmented adipose tissue was obtained through the Lipogems® kit and intraarticularly injected after an arthroscopic debridement. Visual analogue scale for pain, Tegner score, Knee Injury and Osteoarthritis Outcome score subscales variations were assessed from baseline to 3, 6, 12, 24 and 48 months of follow-up.

Results

Forty-one patients were evaluated up to 6 months of follow-up, 39 patients up to 24 months of follow-up and 38 patients up to 48 months of follow-up. Three underwent knee replacement surgery during the time of the study. All the clinical scores analyzed achieved statistically significant changes up to the last follow-up.

Conclusions

A single intra-articular knee injection of micro-fragmented adipose tissue following arthroscopic debridement is able to provide significant clinical benefits in patients affected by knee OA up to 4 years of follow-up.

The present clinical study was registered on clinicaltrials.gov (no. NCT06545266).

Level of Evidence

Level IV case series.

Purpose

Subchondral bone marrow lesions (BMLs) are present in a wide range of pathologies with different prognoses. Thus, a careful diagnosis is mandatory to address them with the proper treatment. The aim of this review was to examine BMLs aetiology and their relationship with biomechanical and biological factors, to identify BMLs and help clinicians to properly recognize and treat each of these common alterations.

Discussion

Each pathological pattern is determined by different aetiologic factors, which may act alone or synergically in determining the BML. These factors include major or minor trauma, bone tissue alterations, altered joint load distribution, coagulopathies, and hormonal alterations. This narrative review encompasses these patterns and factors providing a nosographic and etiopathogenetic framework for subchondral BMLs in the knee.

Conclusion

While the field is still heterogeneous in the definition of the nosographic framework of BMLs, there is a trend with the convergence towards a common terminology, which could help to shed more light on the complex and varied field of BMLs. Future studies should focus on better understanding the etiopathogenetic mechanisms, which can concur with the development of BML from one side, and, on the other hand, may represent targets for future treatments to address BMLs and preserve or restore the osteochondral unit.

Level of Evidence

Expert Opinion, Level V.

Purpose

To assess platelet-rich plasma (PRP) changes in platelet and leucocyte count, insulin-like growth factor 1 (IGF-1), and interleukin 6 (IL-6) concentration after bilateral low-load knee extensions under blood flow restriction (BFR).

Methods

The present randomised controlled trial protocol will include two groups: the intervention group, which will undergo bilateral knee extensions under BFR, and the control group, which will perform bilateral knee extensions without BFR. Participants will be randomly allocated in a 1:1 ratio. Twenty-two healthy individuals will be enrolled if the predefined inclusion criteria are met: (1) males, (2) ages 18–40, (3) Tegner activity level ≥5 and (4) with no musculoskeletal conditions that would interfere with exercise. Exclusion criteria include (1) individuals with systemic inflammatory diseases, (2) cardiovascular risk factors, (3) any blood dyscrasia, (4) Tegner Activity scale scores <5, (5) under nonsteroidal anti-inflammatory drugs and aspirin treatment within one week before testing or (6) that had previously performed exercises on the testing day. The participant will perform low-load bilateral knee extensions under BFR following a standard protocol of 30-15-15-15 repetitions of consecutive sets with 30-s rest intervals at 80% of limb occlusive pressure and 30% of 1-RM load. PRP platelet and leucocyte count, IGF-1 and IL-6 concentration measurements (via flow cytometry, chemiluminescence testing and immunochromatography, respectively) will be conducted before exercise and 10, 20 and 30 min after the intervention.

Results

The expected outcome is that the standard protocol of low-load bilateral knee extensions under BFR will increase the platelet and leucocyte count, IGF-1 and IL-6 in the PRP preparation.

Conclusion

The current protocol allows the study of an enhanced PRP formulation for its potential implementation in multiple sports injuries.

The increased rate of anterior cruciate ligament (ACL) tears has led to a greater number of revisions. Revision surgery can be performed in one or two stages. Single-stage revision ACL reconstruction (ssRACLR) may be performed when prior tunnels can be re-used or bypassed whereas a two-stage procedure is indicated when bone grafting of dilated tunnels prior to revision is necessary. While both approaches have shown similar functional outcomes and failure risk, ssRACLR is preferred, when possible, to avoid the increased morbidity, inconvenience and cost associated with two-stage RACLR. In adequately planning for RACLR, a surgeon should investigate the mechanism and timing of injury as well as the previous graft selection, associated pathology and the tunnel placement and size. It is especially important to obtain radiographs and three-dimensional imaging including magnetic resonance imaging (MRI) and computed tomography (CT), which allow the surgeon to accurately evaluate the entire tunnel architecture to determine surgical staging. Following a detailed assessment of the pathoanatomy, the surgeon may determine graft and hardware type, tunnel placement and utilization of lateral extra-articular tenodesis (LET) and other procedures. In our experience, ssRACLR can be carried out for over 90% of revision cases with creative pre-operative planning using autograft with bone plug(s), divergent tunnel creation on the femur (when necessary) and convergent tunnel creation on the tibia (when appropriate) and suspensory or interference fixation as needed. In revision scenarios, we believe that autografts with bone plugs provide the best opportunity for graft healing and incorporation and that LET can be a useful adjunct to reduce re-tear rates. The purpose of this review is to report on the preoperative considerations and surgical techniques for performing ssRACLR, as well as the outcomes.

Level of Evidence

Level V expert opinion.

Purpose

Gap-balanced total knee arthroplasty (TKA) technique relies on initial ligament evaluation, particularly in patient-specific implantation using computer-assisted technologies. This cadaveric study aimed to compare the reproducibility and reliability of medial and lateral gap measurements between manual stress testing and dynamic ligament balancer.

Methods

Initial gap acquisitions were assessed from eight cadaveric knees (four specimens) during the same navigated TKA procedure by five differently skilled surgeons (three seniors and two juniors). Medial and lateral gaps were sequentially acquired from extension to maximum knee flexion, applying manual stress prior to any bone cuts (conventional technique), and using intra-articular tensioning device placed between the tibial cut and the native femur (instrumented technique). Reproducibility was assessed using intraclass correlation coefficient (ICC), stratified by the measurement technique, the type of gaps and the operator experience. Differences in gaps (mm) between techniques were assessed using the Bland and Altmann method.

Results

The instrumented technique showed higher ICCs than the conventional technique for medial and lateral gaps (0.87 vs. 0.60, P = 0.002, and 0.92 vs. 0.25, p < 0.0001, respectively), and showed no difference in ICCs between medial and lateral gap acquisitions (0.87 vs. 0.92, p = 0.8). Senior surgeons achieved higher ICCs than juniors, while non-significant with both techniques. Differences in gaps between techniques increased with knee flexion angle (0.8, 2.8 and 3.5 mm at 10°, 45° and 90° of flexion angle, respectively) and decreased with the operator experience (p = 0.003).

Conclusion

The instrumented balancing technique offered better reproducibility than using manual valgus and varus stress, when measuring medial and lateral gaps. Tensioning devices may play a significant role in enhancing initial gap acquisition, disregarding the flexion angle and the operator experience.

Level of Evidence

Level IV (observational study involving cadaveric specimens).