Midterm outcomes following anatomic-based popliteus tendon reconstructions

Open Popliteus Tendon Reconstruction Using a Hamstring Tendon Autograft

The popliteus tendon plays a critical role in restraining the tibia against external rotation. It is often injured in the setting of posterolateral corner injuries. However, it is rarely injured in isolation from other structures of the posterolateral corner. This Technical Note describes an open anatomic reconstruction of the popliteus tendon. Although several techniques exist, this technique has been biomechanically validated and shown to have good outcomes. An early rehabilitation protocol focused on protected range of motion, edema control, quadriceps strengthening, and pain control is essential for maximizing patient outcomes.

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.

Nerve and Arterial Supply Pattern of the Popliteus Muscle and Clinical Implications

Introduction. The aim of this study was to investigate the nerve and artery supply and the tibial attachment of the popliteus muscle using anatomical methods. Methods. Forty-four nonembalmed and embalmed extremities were dissected for this study. To measure the attachment area of the popliteus, the most prominent points of the medial epicondyle of the femur and the medial malleolus of the tibia were identified before dissection. A line connecting these two prominent points was used as the reference line, with the most prominent point of the medial epicondyle of the femur as the starting point. This study also investigated the area where the popliteus attaches to the bone and the points where nerves and arteries enter the popliteus muscle when it is divided into three equal parts in the coronal plane. Results. The mean length of the reference line was $34.6\pm 2.1\text{cm}$ . The origin of the popliteus was found to be at a distance of 16.6% to 35.2% on the tibial bone from the proximal region. The popliteus was innervated by only the tibial nerve in 90% of the cases and by the tibial and the sciatic nerves in the remaining 10% of the cases. The inferior medial genicular artery and the posterior tibial artery supplied blood to the popliteus in 90% and 65% of the cases, respectively. When the popliteus muscle was divided into three equal parts in the coronal plane, the nerve and the artery were found to enter the muscle belly in zones II and III and zones I and II in 92% and 98% of the specimens, respectively. Discussion. The anatomical investigation of the popliteus in this study will help identify patients with clinically relevant syndromes.

The clinical outcome of minimally invasive popliteal tendon recess procedure is comparable to arthroscopic popliteal tendon reconstruction in patients with type A posterolateral rotational instability

PURPOSE

To compare the objective and subjective clinical outcome of minimally invasive popliteal tendon (PT) recess procedure versus arthroscopic PT reconstruction, combined with posterior cruciate ligament reconstruction in patients with Type A posterolateral rotational instability (PLRI). The hypothesis was that the two techniques had comparable clinical outcomes.

METHODS

Between 2012 and 2017, patients who were eligible for inclusion in this study if they (1) had Type A PLRI according to Fanelli's classification with posterior tibial translation > 12 mm on stress radiography and side-to-side difference of dial test external rotation > 10°, (2) PT peel-off lesion or laxity with structural integrity (3) were followed for a minimum of 2 years with examination under anesthesia (EUA) and stress radiograph results. Evaluation included subjective scoring, knee stability examinations and second-look arthroscopic lateral gutter drive-through (LGDT) test. Patients who underwent PT recess procedure were designated as Group A, while patients who underwent arthroscopic PT reconstruction were labelled as Group B. The differences between the two groups were analyzed.

RESULTS

A total of 61 eligible patients with a minimum follow-up time of 2 years were evaluated in the present study. At the final follow-up, there were no significant inter-group differences in Lysholm scores (Group A: 69.0 ± 16.5, Group B: 75.8 ± 14.6, ns), Tegner scores [Group A: 2 (1-4), Group B: 3 (1-5), ns], or IKDC subjective scores (Group A: 70.5 ± 13.5, Group B: 71.1 ± 9.1, ns). No significant difference in side-to-side difference on posterior stress radiography (Group A: 4.3 ± 3.8 mm, Group B: 4.7 ± 4.6 mm, P = 0.701), dial test result (Group A: 0.9 ± 4.4°, Group B: 1.6 ± 4.9°, ns) or LGDT test positive rate (Group A: 2/34, 5.9%, Group B: 2/27, 7.7%, ns) was observed.

CONCLUSION

Both minimally invasive PT recess procedure and arthroscopic PT reconstruction significantly improved the knee stability and subjective outcome comparing with preoperative value. In a comparison with arthroscopic PT reconstruction, the recess procedure demonstrated comparable subjective and objective clinical outcome. When both PT reconstruction and PT recess procedure are indicated, the minimally invasive and graft-free recess procedure can be a viable option.

LEVEL OF EVIDENCE

III.

Isolated Popliteus Tendon Avulsion: Fully Arthroscopic Repair with Suture Anchor: A Case Report

CASE

Isolated popliteus tendon avulsion is an extremely rare injury with no consensus in the literature, regarding the therapeutic approach. In our case, the patient presented with rotational instability of the knee, and he was treated surgically. A fully arthroscopic technique with suture anchors was used, and this is the first report of such a repair in the literature. Knee stability was successfully restored, and the patient remains asymptomatic 2 years postoperatively.

CONCLUSION

Isolated popliteus tendon avulsion can result in knee instability. Arthroscopic repair with suture anchors is an efficient way of treatment.

Editorial Commentary: Those Who Don't Know History Are Condemned to Repeat It-What Are the Next Steps to Improve Posterolateral Knee Outcomes?

Two decades ago, it was not uncommon to call the posterolateral corner of the knee the "dark side of the knee." This was because there were few quantitative anatomic data, no anatomic-based reconstructions, and a high rate of clinical outcome failures. Most nonanatomic posterolateral reconstruction procedures at the time commonly resulted in significant recurrent increases in varus gapping and significant overconstraint in external rotation. Postoperative protocols for treating these injuries were designed to often either cast or immobilize the operative knee for 2 to 6 weeks, which resulted in a higher incidence of arthrofibrosis. In addition, missed or neglected posterolateral corner injuries were frequently the cause of failed anterior and posterior cruciate ligament reconstruction graft failures. Anatomic-based posterolateral corner reconstructions have now been validated clinically to significantly improve patient outcomes. The next steps in improving patient outcomes would be to further refine these anatomic-based techniques, improve postoperative rehabilitation protocols, and ensure that future outcome studies have both patient-reported outcomes and objective data with stress radiographs to confirm that we are building a better mousetrap to treat this pathology.

Midterm Clinical Outcome of Combined Posterior Cruciate Ligament Reconstruction and Posterolateral Corner Surgery Using Second-Look Arthroscopic "Lateral Gutter Drive-Through" Test as an Adjunctive Evaluation

Objectives

The arthroscopic “lateral gutter drive‐through” (LGDT) sign is reported to diagnose popliteus tendon (PT) injury with high sensitivity and specificity. However, no study has provided a postoperative evaluation of combined posterior cruciate ligament (PCL) and posterolateral corner (PLC) injuries using the LGDT test.

Methods

From January 2012 to January 2015, a total of 80 consecutive patients who underwent combined PCL reconstruction and PLC surgeries were identified. Fifty eligible patients were included in this study for evaluation with subjective scoring systems, physical examinations, posterior and varus stress radiographs, and second‐look arthroscopic surgeries during hardware removal operation.

Results

Forty‐nine patients were available for a mean of 31.5 ± 9.3 months follow‐up (range, 24.0–81.0 months). In terms of PLC injury pattern, there were 27 type A, 10 type B, and 12 type C patients, with 21 acute cases and 28 chronic cases. At the final follow‐up, subjective scores were all significantly improved. The side‐to‐side difference (SSD) of posterior tibial translation (PTT) improved from 18.4 ± 9.2 mm (range, 12.9–25.6 mm) to 5.2 ± 5.0 mm (range, −5.0−18.5 mm, P < 0.001), and the SSD of tibial external rotation by dial test (ER) decreased from 18.0° ± 14.4° (range, 13.0°–22.0°) to 1.2° ± 7.5° (range, −9.0°–22.0°, P < 0.001). In patients with type C injury, the SSD of the lateral opening decreased from 14.2 ± 6.6 mm (range, 22–10.2 mm) to 0.9 ± 3.1 mm (range, −4.4‐6 mm, P < 0.001). In a comparison between patients with positive and negative LGDT signs, the LGDT‐negative patients had significant superiority in subjective scores, SSD of PTT, and SSD of ER. The sensitivity and specificity of the LGDT test in detecting postoperative posterolateral rotational instability (PLRI) were calculated as 100% and 88.4%, respectively.

Conclusions

In the series of surgically treated patients with PCL and PLC injury: (i) patients had improved subjective and objective clinical outcome after combined PCL reconstruction and PLC surgery at a minimum of 24‐months follow‐up; and (ii) second arthroscopic LGDT sign testing had high sensitivity and specificity in detecting postoperative PLRI, and a positive LGDT sign was related with inferior subjective and objective results.

The Clinical Outcome of Arthroscopic Versus Open Popliteal Tendon Reconstruction Combined With Posterior Cruciate Ligament Reconstruction in Patients With Type A Posterolateral Rotational Instability

PURPOSE

To compare the objective and subjective clinical outcomes of arthroscopic versus open popliteal tendon (PT) reconstruction combined with posterior cruciate ligament reconstruction in patients with type A posterolateral corner injury.

METHODS

From January 2012 to March 2016, patients were eligible for inclusion in this study if they (1) had type A posterolateral rotational instability according to Fanelli's classification, (2) underwent arthroscopic (group A) or open PT (group B) reconstruction, and (3) were followed for a minimum of 2 years with second-look arthroscopic findings. For evaluation, this study used subjective scoring systems (Lysholm, Tegner, and International Knee Documentation Committee subjective scores), knee stability examinations (side-to-side differences of tibial external rotation angle by dial test and posterior and varus stress radiographs), and second-look arthroscopic lateral gutter drive-through tests during hardware removal operations.

RESULTS

A total of 38 patients were included in the study. The mean follow-up period was 31.0 ± 5.8 months in group A (n = 21) and 34.8 ± 12.7 months in group B (n = 17). At the final follow-up, all subjective and objective evaluation results were significantly improved compared with the preoperative condition. There were no significant intergroup differences in Lysholm score (group A, 72.7 ± 17.2; group B, 67.2 ± 14.2; P = .818), Tegner score (group A, 2; group B, 2; P = .710), or International Knee Documentation Committee subjective score (group A, 73.0 ± 13.8; group B, 69.7 ± 20.7; P = .561) at the final follow-up. In terms of objective evaluations, there was no difference in side-to-side difference of posterior stress radiography (group A, 4.0 ± 3.2 mm; group B, 5.0 ± 2.9 mm; P = .336) or lateral gutter drive-through test positive rate (group A, 1/21, 4.8%; group B, 2/17, 11.8%; P = .426).

CONCLUSION

Both arthroscopic and open PT reconstruction significantly improved the knee stability and subjective outcome of patients with type A posterolateral rotational instability. In comparison with the open procedure, the arthroscopic PT reconstruction showed similar subjective and objective clinical outcomes.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

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

Arthroscopic popliteus tendon reconstructions were found to be equally as efficacious as open popliteus reconstructions in restoring external rotation stability. However, when the procedure was combined with a posterior cruciate ligament (PCL) reconstruction, the PCL reconstruction still had increases of 4 to 5 mm of posterior tibial translation in side-to-side differences on posterior stress radiographs. Thus, the goal of restoring stability for combined popliteus tendon and PCL reconstructions is still elusive.