Editorial Commentary: Arthroscopic Outcomes Are Equal to Open Popliteus Tendon Reconstructions, but Do Not Forget That the Goal Is a Stable Posterior Cruciate Ligament Reconstruction

Drilling the tibial tunnel in an arthroscopic popliteus bypass from the anteromedial tibial cortex decreases risk of popliteal vascular injury

Purpose

Drilling the tibial tunnel in tibiofibular-based posterolateral corner (PLC) reconstructions is usually performed with a starting point from Gerdy's tubercle. Drilling the tunnel starting from the anteromedial tibial cortex could reduce the risk of popliteal neurovascular (PNV) injury. The purpose of this study is to assess the distance on Magnetic Resonance Imaging Scans (MRI) of the PNV bundle and peroneal nerve (PN) to these two different tunnel trajectories.

Methods

A total of 87 MRI scans were assessed. The ideal exit point of the tibial tunnel in PLC reconstructions was marked. We added 10 mm from this point in a straight posterior and in an oblique trajectory, mimicking the two different tunnel trajectories and measured the distance to the PNV bundle and PN from these two points.

Results

The mean distance of the tip of the guide wire drilled with a trajectory from Gerdy's tubercle to the PNV bundle and the peroneal nerve was respectively 13.2 mm (SD = 3.96) and 17.7 mm (SD = 4.39). The mean distance of the tip of the guide wire drilled with a trajectory from the anteromedial tibial cortex to the PNV bundle and the PN was respectively 19.6 mm (SD = 4.19) and 12.2 mm (SD = 3.96).). Drilling in a trajectory from the anteromedial tibial cortex significantly increases the distance to the PNV bundle (p < 0.001).

Conclusion

Tibial tunnel drilling in a tibiofibular based PLC reconstruction from the anteromedial tibial cortex significantly increases the distance to the popliteal artery but with a decreased distance to the peroneal nerve.

Level of evidence

level IV.

Most Publications Regarding Arthroscopic Treatment of Posterolateral Corner Injuries of the Knee Have a Low Level of Evidence and Provide Limited Information to Determine the Most Effective Treatment

Purpose

To examine the Level of Evidence and overall quality of studies addressing arthroscopic posterolateral corner reconstructions of the knee.

Methods

A search was performed using the PubMed/Medline, Web of Science, and Google Scholar databases for all studies investigating arthroscopic treatment of posterolateral corner injuries of the knee. Studies reporting outcomes or describing arthroscopic techniques for treatment of posterolateral corner injuries of the knee were the focus of this analysis. Clinical as well as biomechanical and cadaveric studies were included. Studies only investigating open techniques were excluded. Two independent reviewers determined the level of evidence for each included study using the criteria established by the Journal of Bone and Joint Surgery and scored each clinical study from 0 to 100 based on 10 criteria from the modified Coleman Methodology Score.

Results

Twenty-four studies matched the inclusion criteria. There were 6 cadaveric technique descriptions, 6 clinical technique descriptions, 3 biomechanical studies, 4 technical repair descriptions, and 5 clinical outcome studies. Thirty-eight percent of all studies were of Level V evidence. Fifty percent of studies were of Level IV evidence, and 12% of studies were of Level III evidence. The mean modified Coleman Methodology Score for the clinical studies was 43 ± 11.4, which is regarded as poor, mainly due to the limited number of patients and the retrospective nature of the studies.

Conclusions

Most studies addressing arthroscopic posterolateral corner reconstruction of the knee are of low level of evidence and provide limited information about the best treatment options.

Clinical Relevance

The number of publications on arthroscopic posterolateral corner reconstruction techniques continues to rise. This systematic review evaluates the level of evidence of these studies.

The treatment of posterolateral knee instability with combined arthroscopic popliteus bypass and PCL reconstruction provides good-to-excellent clinical results in the mid-term follow-up

PURPOSE

The purpose of this study was to evaluate the clinical outcomes of patients who were treated with an arthroscopic popliteus bypass (PB) technique, in cases of a posterolateral rotational instability (PLRI) and a concomitant posterior cruciate ligament (PCL) injury of the knee.

METHODS

This was a retrospective case series in which 23 patients were clinically evaluated after a minimum of 2 years following arthroscopic PB and combined PCL reconstruction. Lysholm, Tegner and Knee Injury and Osteoarthritis Outcome scores as well as visual analog scales (VAS) for joint function and pain were evaluated. Posterior laxity was objectified with stress radiography and a Rolimeter examination. Rotational instability was graded with the dial test.

RESULTS

23 patients were available for follow-up, 46.0 ± 13.6 months after surgery. The median time interval from the initial injury to the surgery was 6.0 (3.5;10.5) months. The postoperative Lysholm Score was 95.0 (49-100); the Tegner Score changed from 6.0 (3-10) before the injury to 5.0 (0-10) at the follow-up examination (p = 0.013). The side-to-side difference on stress radiography (SSD) of posterior translation changed from 10.4 (6.6-14.8) mm before the injury to 4.0 (0.2-5.7) mm postoperatively (p < 0.01). Rotational instability was reduced to grade A (82.6%) or B (17.4%) (IKDC). The Rolimeter SSD was 2.0 (0-3) mm at the follow-up examination. VAS Function 0 (0-5), VAS pain 0 (0-6).

CONCLUSIONS

The arthroscopic PB graft technique provided good-to-excellent clinical results in the mid-term follow-up in patients with type A PLRI and concomitant PCL injury. However, an exact differentiation of lateral, rotational and dorsal instabilities of posterolateral corner (PLC) injuries is crucial, for the correct choice of therapy, as cases with lateral instabilities require more complex reconstruction techniques. Arthroscopic posterolateral corner reconstruction is a safe procedure with a high success rate in the mid-term follow-up.

LEVEL OF EVIDENCE

IV.