Youn-Soo Park

Background: Intraoperative periprosthetic femoral fractures (IPFF) represent a concerning and often under-recognized complication in total hip arthroplasty (THA). Although several risk factors have been reported, their association with specific femoral morphology and stem geometry has not been fully addressed. This study aimed to identify the incidence and risk factors for IPFF in THA using cementless tapered stems. Methods: A retrospective review was conducted on 3137 primary THAs (2622 patients) performed with cementless tapered stems at a single institution between February 2011 and August 2018. Femoral morphology was classified according to the Dorr types; A (1425 hips, 45.4%), B (1542, 49.2%), and C (170, 5.4%). Femoral stems were categorized as flat, rectangular, or quadrangular tapered designs. The occurrence of IPFF was identified through surgical records and postoperative radiographs. Multivariate regression analysis was performed to identify independent risk factors for IPFF. The mean age at THA was 55 years (range, 15–96), and 52.9% of the patients were women. Results: The overall incidence of IPFF was 2.2% (69 hips). Non-displaced cracks in the proximal metaphysis (58 hips, 84.1%) were the most common type of fracture. The incidence of IPFF was significantly higher in Dorr type A (3.0%) and type C (4.7%) femurs compared with type B (1.2%) femurs. Multivariate regression revealed that female sex (odds ratio [OR], 1.752; p = 0.032) and Dorr type A (OR, 2.898; p < 0.001) and type C (OR, 4.530; p < 0.001) were significantly associated with IPFF. Additionally, the use of quadrangular tapered stems was associated with a higher risk compared with flat tapered stems (OR, 7.382; p < 0.001). Conclusions: Dorr type A and C femurs, along with female sex and the use of quadrangular tapered stems, were significant risk factors for IPFF. Our findings suggest that preoperative consideration of individual femoral morphology and careful selection of stem design are essential to mitigate the risk of IPFF in THA using cementless tapered stems.

Background Multiple epiphyseal dysplasia (MED) is an inherited condition characterized by delayed and irregular ossification of the epiphyses that can lead to premature osteoarthritis. This study aimed to report the long-term outcomes of total hip arthroplasty (THA) in patients with MED. Methods We reviewed THAs performed in MED patients at a single institution between April 1997 and May 2014. Of the 57 identified patients (103 hips), 48 (88 hips) who satisfied a minimum follow-up of tenyears were included. The Harris Hip Score was used for clinical evaluation. Hip radiographs were analyzed to evaluate changes in limb length, femoral offset, and implant stability. The mean age was 50 years and the mean follow-up duration was 16 years. Results The mean Harris Hip Score improved from 43 preoperatively to 91 at the final evaluation (P < 0.001). Limb length and femoral offset increased after surgery by a mean of 16.1 (P < 0.001) and 7.3 mm (P < 0.001), respectively. Seven (8.0%) intraoperative periprosthetic femoral fractures were identified, but no postoperative fractures were identified. Overall, three revision surgeries were performed; two for osteolysis and one for periprosthetic joint infection. No dislocations or major neurovascular injury were observed. Implant survivorship free of any revision was 95.9% at 16 years. Conclusion THA performed in patients with MED demonstrated excellent clinical outcomes with high implant survivorship at a mean follow-up of 16 years. Our findings suggest that THA is an effective and durable option for treating osteoarthritis secondary to MED.

Background: Sciatic neuropathy can result from pressure, injury, or inflammation around the sciatic nerve. In rare instances, sciatic neuropathy is caused by an intraneural ganglion cyst (IGC) originating from the hip joint. However, an effective treatment modality for this condition has not yet been established. The purpose of the present study was to evaluate the clinical and radiographic outcomes of hip arthroscopy for the treatment of IGCs involving the sciatic nerve. Methods: We reviewed the records on a consecutive series of hip arthroscopy procedures that had been performed by a single surgeon for the treatment of sciatic IGCs between July 2016 and February 2022. Thirteen Asian patients (13 hips) with symptomatic sciatic neuropathy were included. During arthroscopic surgery, IGCs were decompressed by enlarging their periarticular connection. Magnetic resonance imaging (MRI) and electrodiagnostic evaluation were routinely performed. The visual analog scale (VAS) for pain and modified Harris hip score (mHHS) were used for clinical evaluations. The mean age at the time of surgery was 57 years (range, 23 to 72 years), and the mean duration of follow-up was 41 months (range, 24 to 87 months). Results: The mean VAS score decreased from 8.3 preoperatively to 1.9 at the latest evaluation (p < 0.001). Satisfactory pain relief was reported by 12 patients (92%), including 9 patients (69%) who had complete remission. Four of the 6 patients with sensory impairment and 3 of the 4 patients with motor weakness reported complete recovery. The mean mHHS improved from 51.5 to 94.1 (p < 0.001). In MRI comparisons, the mean largest diameter and length of IGCs decreased from 2.6 to 0.5 cm (p < 0.001) and from 6.8 to 0.6 cm (p < 0.001), respectively. IGCs completely disappeared on MRI in 9 patients (69%). The latest electrodiagnostic studies confirmed improvement in all 12 patients with preoperative abnormalities. One patient (8%) with symptomatic recurrence was successfully treated with revision arthroscopic decompression. Conclusions: In patients with sciatic neuropathy, the possibility of IGCs arising from the hip should be considered. Our findings suggest that arthroscopic hip surgery is a less-invasive and more-effective treatment for relieving neuropathic pain and neurological deficits associated with sciatic IGCs. Level of Evidence: Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.

Purpose Hip resurfacing arthroplasty (HRA) is recommended for younger patients seeking higher levels of activity. However, femoroacetabular cup impingement (FACI) between the femoral neck and acetabular prosthesis remains a concern. This study aimed to determine the incidence, risk factors, and prognostic consequences of FACI after HRA. Methods This study included 242 HRAs performed at a single institution. Three types of implants with different cup articular arc angle (CAAA) values were used. FACI was defined as indentation or spur formation at the femoral neck corresponding to the ridge of the acetabular cup. Multivariate regression analyses were conducted to identify risk factors for FACI. Clinical outcomes were compared between groups with and without impingement. The mean follow-up duration was 12 years (range, 2‒19). Results FACI was identified in 87 out of 242 HRAs (36%). Multivariate regression analysis showed that FACI was associated with the use of implants with a greater CAAA (P < 0.001). At the latest evaluation, the mean Harris Hip Score (94 vs. 93; P = 0.405) and the incidence of groin pain (16.1% vs. 14.8%; P = 0.795) were similar between the groups with and without FACI. Implant survivorship free of any revision was 94.5% in the FACI group and 89.8% in the non-FACI group at 12 years (log-rank, P = 0.165). Conclusion This study identified that the incidence of FACI after HRA was 36%. Implants with greater CAAA were associated with a higher risk of impingement. However, radiographic FACI was not associated with adverse clinical outcomes of HRA after a mean follow-up of 12 years.

Background Recurrent dislocation is a difficult complication after total hip arthroplasty (THA). This study aimed to report the clinical and radiographic outcomes of revision THA using the modular dual mobility (MDM) acetabular system to treat recurrent dislocation. Methods Between March 2015 and February 2019, 34 revision THAs were performed using the MDM system for treating recurrent dislocation in a single institution. Of these, 32 revision THAs (32 patients) that satisfied a minimum follow-up of one year (mean, 4 years) were included in this study. Patient-reported outcomes, complication rates, and radiographic results were evaluated. Results Seventeen patients (53.1%) had lumbar degenerative kyphosis, and six (18.8%) had surgically fused lumbar spines during the index operation. All acetabular components were revised, whereas femoral stems were retained in 29 patients (90.6%). No redislocation or intraprosthetic dislocation was noted after revision. One additional revision was required for acetabular loosening with periprosthetic joint infection. No additional revision was performed for aseptic loosening. A partial radiolucent line was found in two hips (6.3%) confined to one acetabular zone. Conclusions Revision THA using the MDM system was effective in treating recurrent dislocation in a group of patients with a high prevalence of lumbar spinal pathology. During a mean follow-up of 4 years, one additional revision THA was performed for septic loosening and none for aseptic loosening.

Purpose: Increased blood loss remains a major drawback of simultaneous bilateral total hip arthroplasty (SBTHA). We examined the effects of disusing closed suction drainage (CSD) on postoperative blood loss and transfusion requirement in cementless SBTHA. Methods: A retrospective cohort study was conducted with a consecutive series of cementless SBTHAs performed by a single surgeon between January 2014 and March 2017. The surgeon routinely used CSD until May 2015 and refrained from CSD in all primary THAs thereafter. This study included SBTHAs with intravenous administration of tranexamic acid (TXA). Postoperative hemoglobin drop, blood loss, transfusion rate, pain scores, complication rates, and implant survivorships were compared between the groups of SBTHA with and without CSD. The minimum follow-up duration was 1 year. Results: Among the 110 patients (220 hips), 46 (92 hips) and 64 (128 hips) underwent SBTHA with and without CSD, respectively. Maximum hemoglobin drop (mean, 4.8 vs. 3.9 g/dL; P = 0.001), calculated blood loss (mean, 1530 vs. 1190 mL; P<0.001), transfusion rate (45.7% vs. 21.9%; P = 0.008), and length of hospital stay (mean, 6.6 vs. 5.8 days; P = 0.004) were significantly lower in patients without CSD. There were no significant differences in postoperative pain scales and wound complication rates. The mean Harris Hip scores at final follow-up (92.5 vs. 92.1; P = 0.775) and implant survivorships with an end-point of any revision at 4 years (98.9% vs. 98.4%; log-rank, P = 0.766) were similar between groups. Conclusions: Disusing CSD significantly reduced postoperative blood loss and transfusion requirement without increasing postoperative pain and surgical wound complications in cementless SBTHA with concurrent administration of intravenous TXA.