Editorial Commentary: Arthroscopic Hip Ligamentum Teres Reconstruction-Reality or Mythology?

The ligamentum teres (LT) is perceived to contribute to hip stability and proprioception. LT incompetence can lead to pain and instability, which may play a role in chondral damage. Hip arthroscopy plays a role in diagnosing and treating LT tears. Reconstruction of the LT is feasible, but careful attention needs to be paid to tunnel positioning, graft material, graft length, and fixation methods. An anatomic femoral tunnel should exit at the fovea capitis on the femoral side, whereas the location for safe placement of the acetabular attachment is thought to be in the posteroinferior part of the cotyloid fossa. On the basis of a recent study, optimization of the acetabular tunnel can potentially be achieved by drilling from the femoral tunnel aided by 15° of abduction and 15° of internal rotation. The femoral neck-shaft angle and femoral anteversion must be factored in while planning the entry point of the femoral tunnel, and this may vary based on the amount of femoral head distraction during hip arthroscopy.

The current situation in hip arthroscopy.

Hip arthroscopy is an evolving surgical technique that has recently increased in popularity.Although femoroacetabular impingement was an important launch pad for this technique, extra-articular pathology has been described through hip endoscopy.Good clinical results in the medium term will allow improvements in this technique and increase its indications. Cite this article: EFORT Open Rev 2017;2:58-65. DOI: 10.1302/2058-5241.2.150041.

Hip Arthroscopy in the Presence of Acetabular Dysplasia.

PURPOSE: Hip arthroscopy is a well established therapeutic intervention for an increasing number of painful hip conditions. Developmental dysplasia of the hip (DDH) is commonly associated with intra-articular hip pathology. However, some surgeons perceive patients with hip dysplasia as poor candidates for hip arthroscopy. Our aim was to describe early outcomes of arthroscopic treatment for patients with DDH, who also had femoroacetabular impingement (FAI) treated when necessary, and to compare these outcomes against a control group of patients without DDH. METHODS: Prospective case-control study of 68 consecutive hip arthroscopy patients assessed with a modified Harris Hip Score (mHHS) preoperatively and at six weeks, six months, and one year after surgery. Presence of DDH was determined using a standard anteroposterior (AP) pelvic radiograph to measure the centre-edge angle (CEA) of Wiberg, with a CEA < 20º used as threshold for diagnosis of DDH. RESULTS: 12 patients (eight female and four male) with acetabular dysplasia and mean CEA of 15.4º (9º to 19º). The control, nondysplastic group comprised 54 patients (23 females and 31 males) with a mean CEA of 33.1º (22º to 45º). All patients in the dysplastic group had a labral tear and 11 (91.7%) had associated femoral cam impingement lesion addressed at arthroscopy. Our study demonstrates a significant (p=0.02) improvement in outcome in the dysplastic group at one year using the mHHS. CONCLUSION: Hip arthroscopy in the presence of DDH is effective in relieving pain for at least one year after surgery although does not address underlying acetabular abnormality.

Fat pad entrapment at the hip: a new diagnosis.

PURPOSE: To establish if a positive impingement sign in femoroacetabular impingement (FAI) may result from entrapment of the fat pad located at the anterior head-neck junction of the upper femur. This fat pad is routinely removed before any cam lesion excision. METHODS: We report a prospective study of 142 consecutive hip arthroscopies for symptomatic FAI where the aim was to remove the arthroscopically identified area of impingement, not necessarily to create a spherical femoral head. Patients were divided into two groups. Group 1 (n = 92; 34 females, 58 males), where a cam-type bony FAI lesion was identified and excised in addition to the fat pad which overlay it, and Group 2 (n = 50; 29 females, 21 males) where the only identified point of impingement was a prominent fat pad. In this situation the fat pad was excised in isolation and the underlying bone preserved. Patients were assessed preoperatively, at six weeks, six months, one year and two years with a modified Harris hip score (mHHS). RESULTS: Both groups were comparable preoperatively for mean age, mean alpha angle and mean anterior offset ratio. Both groups improved significantly after surgery at all time points. However, Group 1 (fat pad and bone resection) demonstrated 16.0% improvement in mHHS by two years while for Group 2 (fat pad resection only) the improvement was 18.9% (p = 0.628). CONCLUSIONS: The fat pad found at the anterior head/neck junction of the hip joint can be a source of pain and we propose fat pad entrapment as a new, previously undescribed diagnosis. Our findings also suggest that a large number of cam lesions are being excised unnecessarily and that further efforts should be made to understand the role of the fat pad as a source of groin discomfort. LEVEL OF EVIDENCE: Level IV, case series.

Revision hip arthroscopic surgery: outcome at three years.

PURPOSE: This study describes the medium-term results of revision hip arthroscopy. METHODS: Patients with persistent hip pain and a positive impingement sign were considered for revision surgery after the exclusion of other causes of groin pain. Seventy-four consecutive patients were prospectively assessed using the modified Harris hip score for a period of 3 years after surgery. Of the 74 patients, 11 had inadequate follow-up data; thus, a total of 63 patients were qualified for the study. The mean age at index surgery was 37 years, comprising 27 males and 36 females. RESULTS: Revision surgery was performed at a mean of 3 years from index surgery. Chondral lesion associated with labral re-injury was the most common finding at revision arthroscopy. In contrast to other authors, however, only 31 % of our patients underwent revision for persistent femoroacetabular impingement. The mean pre-operative mHHS for all 63 patients was 54 (SD 14.5). The mean post-operative mHHS was 53 (SD 14.9) at 6 weeks, 62 (SD 17.5) at 6 months, 63 (SD 16.5) at 1 year, 64 (SD 16.5) at 2 years and 59 (SD 16.5) at 3 years (p = n.s., 0.02, 0.045, 0.039 and n.s., respectively). CONCLUSIONS: Revision arthroscopy results in improvement in outcome in the first 3 years after revision surgery with a success rate of 63.4 % at 1 year, falling to 55.6 % by 3 years.

Are crutches required after hip arthroscopy? A case-control study.

Hip arthroscopy provides a less invasive alternative to arthrotomy and has the potential for more rapid rehabilitation. Few guidelines exist for rehabilitation after hip arthroscopic surgery. However, these are not corroborated with evidence of objective outcome measures. In particular, the period for which crutches should be used is imprecisely explained, if explained at all. The purpose of this study was to determine whether or not crutch use is required after hip arthroscopic surgery, and if so, for how long.
 We compare a postoperative regimen of four weeks partial weight bearing on crutches (Group 1, n = 85) with a regimen that permitted patients to fully weight bear immediately after surgery if comfort allowed (Group 2, n = 80). We used the modified Harris hip score (mHHS) as an outcome measure at six weeks and six months after surgery. For Group 1, the mean duration of crutch use was 28.2 days and the mean postoperative mHHS at six weeks and six months showed significant improvement compared with preoperatively. For Group 2 the mean duration of crutch use was 13.4 days and the mean postoperative mHHS at six weeks and six months also showed significant improvement compared with preoperatively. The results demonstrated no significant difference in postoperative mHHS between the two groups at six weeks and six months after surgery.
 There thus appears to be no need to enforce a defined period of partial weight bearing on crutches after hip arthroscopic surgery, irrespective of the procedure undertaken.

Do professional athletes perform better than recreational athletes after arthroscopy for femoroacetabular impingement?

BACKGROUND: Although a large number of athletes' returns to sports after hip arthroscopic surgery for femoroacetabular impingement (FAI), it is not clear if they do so to the preinjury level and whether professional athletes (PA) are more likely to return to the preinjury level compared with recreational athletes (RA). QUESTIONS/PURPOSES: We therefore compared (1) the time taken to return to the preinjury level of sport between professional and recreational athletes; (2) the degree of improvement in time spent in training and competitive activities after arthroscopic surgery for FAI; and (3) the difference in trend of improvement in hip scores. METHODS: We prospectively followed 80 athletes (PA = 40, RA = 40; mean age, 35.7 years; males = 50, females = 30; mean followup, 1.4 years; range, 1-1.8 years) who underwent hip arthroscopy for FAI. We measured the time to return to sports; training time and time in competition; and the modified Harris hip score and the nonarthritic hip score. RESULTS: There was a 2.6-fold improvement in the training time (from 7.8 to 20 hours per week) and a 3.2-fold increase in time in competition (from 2.5 to 7.9 hours per week) 1 year after surgery. The mean time to return to sporting activities was 5.4 months, which was lower for PA (4.2) as compared with RA (6.8). Eighty-two percent (66) (PA = 88% [35] versus RA = 73% [29]) returned to their preinjury level of sport within 1 year of surgery. CONCLUSIONS: The data suggest PA may show quicker return to sports than RA but the hip scores and rate of return to sports are similar.

The accuracy of magnetic resonance arthrography in hip arthroscopic labral revision surgery.

The interpretation of a magnetic resonance arthrogram (MRA) after a labral tear has been surgically treated can be challenging and there is no published evidence on its accuracy. The aim of this study was to evaluate the MRA accuracy in identifying labral pathology after hip arthroscopy. We reviewed 60 patients who had undergone a revision hip arthroscopy. Patients were divided into two groups. First, a study group (n = 40), which included patients who had undergone arthroscopic labral surgery at index operation. Secondly, there was a control group (n = 20), for patients who had not undergone labral surgery at index procedure. Findings regarding labral pathologies at MRA and at revision surgery were recorded. Sensitivity for MRA after hip arthroscopy was 53% and 71% in the study and control groups, respectively; specificity was 50% and 92%, positive predictive value was 81% and 83%, negative predictive value was 21% and 86% and accuracy was 53% and 85%. We conclude that the MRA is not reliable after hip arthroscopy where a labral tear has been addressed. When a labral tear has been repaired or partial labral excision has been performed, a postoperative MRA may inaccurately diagnose the presence of a persistent, recurrent, or unhealed tear.

Does the modified Harris hip score reflect patient satisfaction after hip arthroscopy?

BACKGROUND: No published studies have explored the relationship between commonly reported clinical outcomes and patient satisfaction after hip arthroscopy. PURPOSE: To compare the modified Harris Hip Score (mHHS) with patient satisfaction in a prospective study over a 2-year period. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: We reviewed our institutional database for prospectively collected mHHS and patient satisfaction data from 697 patients. Patients were evaluated preoperatively and at 1 and 2 years after surgery. RESULTS: The mHHS correlated with patient satisfaction at 1 year (P < .001, Pearson R = 0.451) and at 2 years (P < .001, Pearson R = .454). Considering scores from excellent to good as positive results and from fair to poor as negative results, sensitivity was 73% at 1 year and 77% at 2 years. Respectively, the specificity was 64% and 73%, positive predictive value 86% and 91%, negative predictive value 45% and 46%, and accuracy 71% and 76%. At 1- and 2-year follow-up, a respective 55% and 54% of patients with fair to poor mHHS were satisfied with the outcome of hip arthroscopy. In contrast, for those patients with an excellent to good mHHS at 1 and 2 years after surgery, 14% and 9%, respectively, were dissatisfied with their outcome. CONCLUSION: Our results show a correlation between patient satisfaction and the mHHS but also demonstrate a limitation of the mHHS as an outcome measure in the prediction of patient satisfaction. Further investigation is required to assess factors beyond current standard orthopaedic clinical outcome measures that may influence patient satisfaction after hip arthroscopy.

Is hip arthroscopy for femoroacetabular impingement only for athletes?

PURPOSE: The aim of this study was to compare the outcome of hip arthroscopy for femoroacetabular impingement (FAI) between athletes and non-athletes. METHODS: The authors prospectively collected data on 122 patients, the largest comparative series reported, who underwent hip arthroscopy for FAI. Of these, 80 actively participated in sporting activities (athletes), while 42 did not (non-athletes). Patients were asked to complete questionnaires for the modified Harris hip score (MHHS), non-arthritic hip score (NAHS), patient satisfaction on a visual analogue scale (VAS). This was collected immediately before surgery, and at 6 weeks, 6 months and 1 year after the procedure. The responses to the MHHS questionnaire were used to calculate the quality-of-life (QoL) score using the Rosser index matrix. RESULTS: A significant improvement in the MHHS, NAHS and QoL was observed at 6 weeks, 6 months and 1 year after surgery (p<0.001). The 6-week MHHS (p=0.01) and NAHS (p=0.04) for the athletes were significantly better as compared with non-athletes. However, the 6-month and 1-year MHHS, NAHS and QoL scores were statistically similar for both groups. CONCLUSIONS: In this large, prospective series of patients we have demonstrated the positive impact of arthroscopic surgery for FAI in both the athletic and non-athletic population. Arthroscopic management of FAI is thus not the sole domain of the athletic patient. Non-athletes can do just as well.

Fluid extravasation during hip arthroscopy.

The amount of fluid that may be lost into the soft tissues during hip arthroscopic surgery is unknown. We measured the volumes of irrigation fluid infused, operating time, fluid pressures and volumes of fluid recovered in 36 therapeutic hip arthroscopies. We excluded those where fluid was lost to the floor, leaving 28 patients. The majority were undergoing surgery for the treatment of femoroacetabular impingement. In 5 patients an intra-articular contrast medium was instilled, in order to establish the likely location of any extravasated fluid. The mean operating time was 68 minutes (31 to 120), and the mean infusion pressure was 46 mm Hg (30 to 70). The mean volume of infused fluid was 9677 ml (95% confidence interval (CI) 7715 to 11638) and the mean volume of fluid recovered was 8544 ml (95% CI 6715 to 10373). The mean fluid extravasation loss into the peri-articular tissues was 1132 ml (95% CI 808 ml to 1456 ml). There was a significant correlation between the volume of extravasated fluid and both the length of operation and the volume of infused fluid used. We had no adverse events in our series. During arthroscopic hip surgery more than a litre of irrigation fluid may be extravasated into the soft tissues. In order to reduce problems related to this we attempt to keep operating times low, and maintain intra-operative fluid pressures as low as possible.

Arthroscopic repair of delaminated acetabular articular cartilage using fibrin adhesive. Results at one to three years.

We describe one- to three-year results of a novel use of fibrin glue in the treatment of cartilage damage by arthroscopy in the hip. This technique uses the microfracture technique and fibrin adhesive to bond delaminated articular cartilage to the underlying subchondral bone. This is generally performed in conjunction with treatment of underlying pathology such as femoroacetabular impingement. Patients were assessed using the modified Harris Hip Score (MHHS) pre- and post-operatively, and statistical significance determined by Student's t-test. We report the mid-term results of 43 patients with femoroacetabular impingement who have undergone this technique for re-attachment of delaminated chondral flaps. There was a statistically significant improvement in MHHS at a mean of 28 months (16 to 42 months) after surgery (p<0.0001). The MHHS for pain improved significantly from 21.8 (95% CI 19.0 to 24.7) pre-operatively to 35.8 (95% CI 32.6 to 38.9) post-operatively (p<0.0001). The MHHS for function also showed significant, although more modest, improvements from 40.0 (95% CI 37.7 to 42.3) pre-operatively to 43.6 (95% CI 41.4 to 45.8) post-operatively (p=0.0006). There were three patients who had early (within 12 months of the index procedure) revision arthroscopy for iliopsoas pathology. Arthroscopic repair of delaminated acetabular articular cartilage using fibrin adhesive is a useful technique in the treatment of early cartilage damage. We have seen encouraging mid-term results, although further studies are warranted.

The prevalence of dysplasia in femoroacetabular impingement.

It is unknown how often femoro-acetabular impingement (FAI) and hip dysplasia co-exist and which is more important in the development of intra-articular lesions such as labral tears. This study identified the prevalence of dysplasia on standard radiographs in a group of 76 consecutive patients with symptomatic FAI. The centre-edge (CE) angle of Wiberg, the acetabular angle (AA) of Sharp, FAI type, offset ratio and posterior wall sign were identified. 63 patients, predominantly young adult males (mean age: 34.6 years; 10:4 male-to-female ratio), met our inclusion criteria. Most females (13:18) showed signs of dysplasia based on the AA. No association of dysplasia with FAI group, offset ratio or posterior wall sign was found. 47% of our patients with FAI also had radiographic evidence of dysplasia (3-15% definite and 9-30% borderline, depending on the angle utilised). Surgery for FAI should therefore take into account the presence of co-existing dysplasia. Conversely, surgery for dysplasia should take into consideration the co-existence of FAI. The prime cause of labral pathology in the presence of dysplasia may be co-existent FAI and the latter problem may demand priority, not the former.

Arthroscopic reconstruction of the ligamentum teres.

We describe a case of arthroscopic reconstruction of the ligamentum teres using a novel technique. This technique is both simple and reproducible. We believe it to be a useful addition to the procedures available to the arthroscopic hip surgeon.

Cyst-like lesion of the acetabular roof - an abnormal finding or an anatomical variant?

Cyst-like lesions are frequently found in the area of the acetabulum on MRI scans. However, their presence is not always abnormal. We report four patients with such lesions found on MRI where, during hip arthroscopy, an area resembling a horseshoe-like extension of the cotyloid fossa was found. Clinicians must be aware that not all cystic acetabular lesions are pathological and may simply represent a normal anatomical or developmental variant of the hip joint. They do not always represent an indication for hip arthroscopic surgery.

Arthroscopic repair of acetabular chondral delamination with fibrin adhesive.

Acetabular chondral delamination is a frequent finding at hip arthroscopy. The cartilage is macroscopically normal but disrupted from the subchondral bone. Excision of chondral flaps is the usual procedure for this type of lesion. However, we report 19 consecutive patients in whom the delaminated chondral flap was re-attached to the underlying subchondral bone with fibrin adhesive. We used the modified Harris hip score for assessment of pain and function. Improvement in pain and function was found to be statistically significant six months and one year after surgery. No local or general complications were noted. Three patients underwent further surgery for unrelated reasons. In each, the area of fibrin repair appeared intact and secure. Our results suggest that fibrin is a safe agent to use for acetabular chondral delamination.

Femoroacetabular impingement and classification of the cam deformity: the reference interval in normal hips.

BACKGROUND AND PURPOSE: Most patients with femoroacetabular impingement (FAI) have a cam deformity, which may be quantified by measuring the alpha angle and anterior offset ratio (AOR). Knowledge of what constitutes a "normal" alpha angle and AOR is limited. We defined the reference intervals of these measurements from normal hips in the general population. PATIENTS AND METHODS: 157 individuals from the general population were reviewed clinically and radiographically. 74 individuals with clinical evidence of hip disease or radiographic evidence of osteoarthritis (OA) were excluded, leaving a study group of 83 individuals (mean age 46 (22-69) years, 44 females) with normal hips. The alpha angles and AORs were measured from cross-table lateral radiographs taken in 15 degrees internal rotation. A validation study consisting of a cadaver study and a measurement reliability study was also performed. RESULTS: The mean alpha angle was 48 degrees in men and 47 degrees in women. The mean AOR was 0.19, the same in men and women. Thus, sexes were combined to derive 95% confidence intervals for the population mean alpha angle (46-49 degrees ) and AOR (0.18-0.20). The 95% reference interval for the alpha angle was 32-62 degrees degrees, and for the AOR it was 0.14-0.24. The validation study confirmed that these measurements were resistant to a reasonable degree of variation in positioning and that the repeatability and reproducibility of the measurements was good. INTERPRETATION: These reference intervals indicate that clinically and radiographically normal hips may have alpha angles and AORs that have previously been considered "abnormal". The thresholds provided by this study will aid classification of individuals involved in longitudinal studies of FAI and OA, and may be of use to the practicing clinician in evaluating the young adult with hip pain.