Hip Outcome Score

Overview:

The HOS is a patient-reported outcome measure developed specifically to evaluate functional limitations in individuals with hip pathology, with a focus on those active enough to be candidates for surgical intervention such as hip arthroscopy. It was designed to be more sensitive to higher levels of function than older hip scales like the Harris Hip Score.

Structure:

The HOS consists of two sub-scales:

1. Activities of Daily Living (ADL) Sub-scale

• Contains 19 items assessing basic functional tasks such as standing, walking on level surfaces, going up and down stairs, putting on shoes and socks, and sitting

• Reflects everyday, lower-demand functional activities

2. Sport Sub-scale

• Contains 9 items assessing higher-demand activities such as running, cutting, jumping, landing, starting and stopping quickly, and sport-specific movements

• Reflects the more dynamic, athletic demands relevant to active populations

Scoring:

Each item is rated on a 5-point Likert scale:

• 4 = No difficulty

• 3 = Slight difficulty

• 2 = Moderate difficulty

• 1 = Extreme difficulty

• 0 = Unable to do

Additionally, patients can mark items as "not applicable" if they do not perform that activity, and those items are excluded from scoring.

Score calculation:

• The total number of points earned is divided by the maximum possible points (excluding N/A items), then multiplied by 100

• This yields a percentage score from 0–100 for each sub-scale

• Higher scores indicate better function

The two sub-scales are reported separately rather than as a combined total score.

Strengths:

• Sensitive to higher levels of function relevant to younger, active patients

Original Literature:

Martin, RobRoy L., Bryan T. Kelly, and Marc J. Philippon. "Evidence of validity for the hip outcome score." Arthroscopy 22.12 (2006): 1304-1311.

Validation Literature:

Thorborg, K., et al. "Patient-Reported Outcome (PRO) questionnaires for young to middle-aged adults with hip and groin disability: a systematic review of the clinimetric evidence." Br J Sports Med (2015): bjsports-2014.

Additional Literature:

Chahal, Jaskarndip, et al. "The patient acceptable symptomatic state for the modified Harris Hip Score and Hip Outcome Score among patients undergoing surgical treatment for femoroacetabular impingement." The American journal of sports medicine 43.8 (2015): 1844-1849.

• For each activity listed, indicate the degree of difficulty you experienced due to your hip condition in the last week.

• If the activity in question is limited by something other than your hip, mark not applicable (N/A).