. 2020 Dec 1;15:573. doi: 10.1186/s13018-020-02112-8

Table 2.

Diagnostic efficacy of arthroscopic assessment according to indications

Indications	PI	AF	GS
Preop diagnosis key points	1. Crepitus and anterior knee pain (AKP) 2. Locking noted with increasing extension at approximately 40° of flexion 3. Resolved with a popping concussion with further extension.	1. Pain and limited ROM (< 90° flexion).	1. Recurrent painful effusion and/or occasional catching. 2. Slightly limited ROM and scattered peripatellar tenderness 3. Joint effusion signs in X-ray and CT.
Intraop diagnosis key points and procedures	1. Dense, well-defined fibrous bands on the backside of quadriceps tendon, which is caught in the femoral box with increasing extension. 2. The impinging soft tissue debrided.	1. Dense adhesions and fibrous bands throughout the joint. 2. Adhesions and bands debrided, controlled arthrolysis and haemostasis.	1. Hypertrophic GS. 2. Occasional synovium entrapment and bleeding. 3. Occasional signs of polyethylene delamination. 4. Synovectomy and haemostasis.

Indications

Preop diagnosis key points

1. Crepitus and anterior knee pain (AKP)

2. Locking noted with increasing extension at approximately 40° of flexion

3. Resolved with a popping concussion with further extension.

1. Pain and limited ROM (< 90° flexion).

1. Recurrent painful effusion and/or occasional catching.

2. Slightly limited ROM and scattered peripatellar tenderness

3. Joint effusion signs in X-ray and CT.

Intraop diagnosis key points and procedures

1. Dense, well-defined fibrous bands on the backside of quadriceps tendon, which is caught in the femoral box with increasing extension.

2. The impinging soft tissue debrided.

1. Dense adhesions and fibrous bands throughout the joint.

2. Adhesions and bands debrided, controlled arthrolysis and haemostasis.

1. Hypertrophic GS.

2. Occasional synovium entrapment and bleeding.

3. Occasional signs of polyethylene delamination.

4. Synovectomy and haemostasis.

Abbreviations: PI peripatellar impingement, AF arthrofibrosis, GS generalized synovitis, ROM range of motion, AKP anterior knee pain, preop preoperative, intraop intraoperative