Can Perineal Post-Free Traction in Hip Arthroscopy Effectively Reduce Perineal Complications?

• Perineal Post-Free Traction (Procedure): Traction achieved with a thoraco-abdominal belt and contralateral groin strap; operating table tilted 10-15° Trendelenburg under fluoroscopy to 8-10 mm joint space. No perineal post is used, eliminating direct perineal pressure.
• Perineal Post Traction (Procedure): Standard traction table with padded perineal post placed against the groin providing counter-traction; affected limb distracted under fluoroscopy to 8-10 mm joint space while contralateral limb is abducted.

Primary outcomes

• The incidence of perineal nerve injury [The first day after surgery]: The incidence of perineal nerve injury included: perineal numbness, pain, soft tissue injury, sexual function and urinary dysfunction.

Secondary outcomes

• The incidence of pain, numbness, soft tissue injury in other places [The first day after surgery]: Lower limb ankle numbness and soft tissue injury; the contralateral groin pain, numbness and soft tissue injury; chest pain, numbness, soft tissue injury with fixed place
• Patients at discharge perineum area incidence of nerve injury [7 days after surgery]: Patients at discharge perineum area incidence of nerve injury include: perineum area numbness, pain, soft tissue injuries, sexual and urinary dysfunction.
• Intraoperative traction time [During surgery (intraoperatively)]: Intraoperative traction time
• Preoperative preparation time [Immediately before surgery (preoperatively)]: Preoperative preparation time
• Operating time [During surgery (intraoperatively)]: Operating time
• The average length of hospital stay after surgery [6 weeks after surgery]: The average length of hospital stay after surgery
• Postoperative joint function assessment [3 months after surgery]: Visual Analog Scale (VAS) (range 0-10; higher scores indicate worse outcomes).
• Postoperative joint function assessment [3 months after surgery]: Modified Harris Hip Score (mHHS) (range 0-100; higher scores indicate better outcomes).
• Postoperative joint function assessment [3 months after surgery]: Hip Outcome Score (HOS) (range 0%-100%; higher scores indicate better outcomes).
• Postoperative joint function assessment [3 months after surgery]: International Hip Outcome Tool 12-Item Questionnaire (iHOT-12), range 0-100, higher scores mean better hip function
• Economic Evaluation - Pain Intensity [14 days after surgery]: This study will conduct an economic evaluation from a healthcare sector and societal perspective. Pain intensity is assessed using the Visual Analog Scale (VAS), a unidimensional measure reported as scores on a 0-100 mm scale. Effectiveness analysis will incorporate this clinical outcome. Safety will be evaluated by monitoring the incidence of adverse events within 3 months postoperatively.
• Economic Evaluation - Hip Function [14 days after surgery]: This study will conduct an economic evaluation from a healthcare sector and societal perspective. Hip function is assessed using the modified Harris Hip Score (mHHS), a measure specifically for hip dysfunction and related symptoms, reported as scores on a 0-100 scale. Effectiveness analysis will incorporate this clinical outcome. Safety will be evaluated by monitoring the incidence of adverse events within 3 months postoperatively.
• Mean Total Healthcare Cost per Patient within 14 Days Postoperatively [Data collection period: From randomization until 14 days postoperatively.]: This is the cost input measure for the economic evaluation, adopting a healthcare system perspective. All direct medical costs related to the surgery and subsequent care from the day of surgery until 14 days postoperatively will be collected via the Hospital Information System. Costs include fees for surgery, anesthesia, medical supplies, hospitalization, medication, imaging and laboratory tests, and additional costs for managing complications. The mean total cost per patient (in Chinese Yuan, CNY) will be calculated separately for the "conventional perineal-post traction group" and the "perineal-post-free traction group".

Sex: All, ages: 15 Years to 60 Years

Inclusion Criteria:

* Aged 15 to 60 years;
* Met the diagnostic criteria of femoroacetabular impingement syndrome (FAI) and indicated for hip arthroscopy based on patient history, symptoms, signs, physical examination, imaging (pelvic anteroposterior view, frog-leg view, CT 3D reconstruction, MRI), and diagnostic injections;
* Able to read and sign the informed consent form.

Exclusion Criteria:

* History of high-energy hip trauma, previous ipsilateral or contralateral hip surgery, avascular necrosis of the femoral head, slipped capital femoral epiphysis, Perthes disease, severe osteoporosis, tumors, acetabular stress fractures, or proliferative or immune hip diseases;
* Diseases causing groin numbness, foot numbness, sexual dysfunction, urinary dysfunction, skin injuries, perineal injuries, nerve injuries, radicular pain, inner or outer thigh numbness;
* Abnormal heart, lung, liver, kidney function, severe coagulation disorders, poorly controlled diabetes, judged by the researcher to have an infection risk;
* Consciousness disorders, psychiatric disorders, or neuromuscular dysfunction affecting lower limb function;
* Active infection foci (systemic or local infectious lesions);
* Pregnancy, lactation, or planned pregnancy during the clinical study period;
* Participation in another clinical trial within the past 3 months;
* Patients deemed unsuitable for the clinical trial by the researcher for other reasons.

• Results publication: Wang L, Zhang L, Wang Y, Wang M, Zheng L, Zhang J, Wu Y, Liu Y, Jiang L, Kang X, Li C. Multicentre randomised controlled trial protocol in China comparing postless hip arthroscopy with conventional perineal post-assisted hip arthroscopy to reduce perineal complications in patients undergoing hip arthroscopy for femoroacetabular impingement: the POSTLESS-HIP trial. BMJ Open. 2026 Sep 28;16(9):e118402. doi: 10.1136/bmjopen-2026-118402. PMID 42805650

• chunbao li, MD, Principal investigator, Chinese PLA General Hospital