Ligamentum teres reattachment post-surgical dislocation of the hip: a case report. Regenerative capacity reaffirming its greater role in hip stability and function?

CASE REPORT

A 15-year-old female patient underwent in 2012 a right hip surgical dislocation to treat a painful hip affecting her quality of life. Her presenting history, clinical examination and radiological investigations culminated to a diagnosis of intra-articular hip pathology: femoroacetabular impingement which included a femoral head with cam-type morphology and associated labrum tearing extending to the lateral acetabular rim as well as minor subspinal impingement.

Pre-operative plain film radiograph of the patient’s pelvis (Fig. 1) and intra-operative clinical photograph documenting her right hip surgical dislocation and treatment including iatrogenic complete rupture of the ligamentum teres (LT) (Fig. 2).

Fig. 1.

Anteroposterior radiograph of the pelvis.

Fig. 2.

Intraoperative photographs demonstrating the right hip surgical dislocation necessitating complete iatrogenic LT rupture and the femoral head treatment.

Post-operative plain film radiograph of the patient’s pelvis were taken after the procedure (Fig. 3).

Fig. 3.

Plain film depicting both hips. Note the standard two screws in the greater trochanter of right femur after the surgical dislocation.

She went on to have an uneventful recovery immediately after her operation. The trochanteric screws were removed 6 months after the index operation. Regular follow up documents a pain free period of about 3½ years post the right hip surgical dislocation with return to sporting activities and satisfactory quality of life.

In early 2016, the patient started experiencing some pain but mainly limitation in her range of motion of her right hip. Plain film of her pelvis was unremarkable (Fig. 4).

Fig. 4.

Anteroposterior radiograph depicting both hips. Note the absence of the trochanteric screws from the right femur.

The deterioration progressed over time as per serial clinical examinations. Radiological studies supported the suspected clinical suspicion of intra-articular adhesions (Fig. 5), a known complication following surgical hip dislocation [13, 14].

Fig. 5.

MRI of right hip (sagittal plane) demonstrating adhesions.

Interestingly, the same magnetic resonance imaging (MRI) in a coronal plane demonstrated an LT in continuity (Fig. 6).

Fig. 6.

MRI of right hip (coronal plane) demonstrating LT in continuity.

By the end of 2016 symptom progression and clinical deterioration of the patient mandated a second look through an arthroscopic procedure.

The patient underwent a right hip arthroscopy on November 2016, 4 years after the index operation. The diagnosis was confirmed and the adhesions were released arthroscopically. The intra-operative range of movement, specifically the internal and external rotation improved significantly. The patient has had so far an uneventful recovery and was discharged from the hospital the day after her operation.

During her hip arthroscopy, the LT was actually attached and there was no evidence of the initial lesion necessitated by the surgical dislocation (Figs 7 and 8).

Fig. 7.

Intra-operative right hip arthroscopy demonstrating LT in continuity.

Fig. 8.

Intra-operative right hip arthroscopy demonstrating satisfactory LT reattachment at the acetabular fossa.

The iatrogenically sectioned LT was in continuity with intact attachments both at the femoral and acetabular sides. The intra-operative photos depict even a somewhat bundled LT appearance as it is described for its native anatomy.

DISCUSSION

This is a case report of an LT in continuity after sectioning by us during surgical dislocation 4 years prior.

Bardakos and Villar [15] reported that Villar had seen four cases of an LT in anatomical continuity after severe injury, including dislocation. O’Donnell et al. [16] have also seen three cases of an apparently intact LT after known rupture and total excision performed previously by them.

This would suggest that the LT does have the potential to heal and reattach. Such ability would reaffirm LT’s greater role in hip kinematics and stability. Yet the biological milieu and mechanical environment required for such regeneration are unknown.

Nowadays, diagnostic or therapeutic arthroscopic hip surgery allows us to take a closer look at this ligament. As we encounter the LT more frequently, we have changed our thinking about its role in hip function.

Our case demonstrates that the LT has the ability to reconstitute after injury. In order to delineate the factors that may lead to this healing potential, we need to focus our attention and understand better the native LT anatomy. And of course define precisely the LT’s role in normal hip joint function and stability at all developmental stages including early development, and during the journey to maturity. That will require better insight at an embryonic state and greater understanding at a molecular level of the makeup of this ligament.

Only then we will be able to speculate with greater confidence on the sequelae of injury of the LT and on those cases where it exhibits abnormal function or it is completely absent. And of course, only then we will be able to design more targeted experiments where the LT is involved in a traumatic insult or it is part of a disease state (i.e. Perthe’s or developmental hip dysplasia).

Finally, the inherent limitations of cases reports are well known. In the background of the anecdotal similar cases from the landmark papers on the topic from Villar et al. and O’Donnell et al. [16] our report is depicting the reconstituted LT during hip arthroscopy 4 years after the index operation. A dynamic video stretching the LT through the range of motion of the hip to determine its functionality would have been interesting. Additionally, we believe that our case report adds validity to these anecdotal aforementioned cases and points to a regenerating/healing pattern of response of the LT to insult when in the appropriate biological and mechanical environment. In the future those conditions remain to be defined more accurately with further scientific experiments and clinical research.

CONCLUSION

Prior to this publication, there have been only anecdotal reports of LT in continuity after severe injuries including dislocation. This is a report of LT in continuity documented during hip arthroscopy 4 years after an index procedure which had required surgical hip dislocation and LT sectioning.

CONFLICT OF INTEREST STATEMENT

None declared.