The majority of<unk>  are isolated ligamentous<unk> . Most patients will relate a history of a traumatic blow to the lateral aspect of the<unk>  (causing a valgus force) or a non-contact valgus force. Acute<unk>  are much easier to diagnose clinically, while chronic<unk>  may be less apparent due to difficulty in differentiating from a lateral<unk>  injury, possibly requiring valgus stress radiographs. Physical Exam The physical exam should always begin with a visual inspection of the joint for any outward signs of trauma. Palpation should follow paying close attention to effusion and subjective tenderness during the exam. The practitioner should also evaluate the contralateral (non-injured)<unk>  to note any differences in gross appearance and landmarks. Palpation should focus specifically on the meniscofemoral and meniscotibial aspects of the sMCL. It has been reported that injury to one versus other has implications for healing, so localization of the site of injury is beneficial. Testing of the<unk>  joint should be done using the following techniques and the findings compared to the contralateral, normal<unk> : *Valgus stress at 0° and 20°- This test puts direct stress on the<unk> <unk>  structures, reproducing the mechanism of injury. Valgus stress testing is done with the patient supine on the exam table. The lower extremity, supported by the examiner, is abducted. The examiner's fingers monitor the<unk>  joint space for gapping while placing the opposite hand on the ankle. The<unk>  is placed in 20° of flexion. The examiner then uses their own thigh as a fulcrum at the<unk>  and applies a valgus force (pulling the foot and ankle away from the patient's body). The force is then used to establish the amount of gapping present within the joint. It has been reported that 20° of flexion is best for isolating the sMCL, allowing the practitioner to establish the degree of injury (see Classification). Additional testing is done at 0° to determine if a Grade III injury is present. *Anteromedial drawer test- This test is performed with the patient supine with the<unk>  flexed to 80-90°. The foot is externally rotated 10-15° and the examiner supplies an anterior and external rotational force. The joint can then be evaluated for tibial anteromedial rotation, taking care to recognize the possibility of posterolateral corner instability giving similar rotational test results. As always, compare the test in the opposite<unk> . *Dial Test (anteromedial rotation test)- This test should be executed with the patient lying both supine and prone. When the patient is supine, the<unk> s must be flexed 30° off the table. The thigh is then stabilized and the foot externally rotated. The examiner watches for the tibial tubercle of the affected<unk>  to rotate as the foot rotates, comparing it to the contralateral<unk> . A positive test will show rotation of greater than 10-15° of rotation compared to the opposite<unk> . This is most easily assessed with a hand placed over the tibia while testing. When the patient is prone, the<unk>  is flexed to 90° and both feet are externally rotated and compared, noting the difference from the non-injured joint. Similar to the anteromedial drawer test, a false positive test can result from a posterolateral corner injury. Testing at both 30° and 90° helps to distinguish between these<unk> : one should monitor where the tibial rotation occurs (anteromedial or posterolateral) in the supine position and also assess for<unk>  or lateral joint line gapping to differentiate between these two<unk> . Classification Grading of<unk>  is dependent on the amount of<unk>  joint space gapping found upon valgus stress testing with the<unk>  in 20° of flexion. Grade I<unk>  have no instability clinically and are associated with tenderness only, representing a mild sprain. Grade II<unk>  have broad tenderness over the<unk> <unk>  and have some gapping with a firm end-point during valgus testing; this represents a partial tear of the ligaments. Grade III<unk>  have a complete ligamentous tear. There will be no end-point to valgus stress testing. The historic quantified definition of grades I, II, and III represented 0–5 mm, 5–10 mm, and >10 mm of<unk>  compartment gapping, respectively. LaPrade et al. reported, however, that a simulated grade III sMCL injury showed only 3.2 mm of increased<unk>  compartment gapping compared to the intact state. Additionally, with the<unk>  in full extension, if valgus stress testing reveals more than 1–2 mm of<unk>  compartment gapping present, a concomitant anterior cruciate ligament (ACL) or posterior cruciate ligament (PCL) injury is suspected. Radiographs Anterior-posterior (AP) radiographs are useful for reliably assessing normal anatomical landmarks. Bilateral valgus stress AP images can show a difference in<unk>  joint space gapping. It has been reported that an isolated grade III sMCL tear will show an increase in<unk>  compartment gapping of 1.7 mm at 0° of<unk>  flexion and 3.2 mm at 20° of<unk>  flexion, compared to the contralateral<unk> . Additionally, a complete<unk>  ligamentous disruption (sMCL, dMCL, and POL) will show increased gapping by 6.5 mm at 0° and 9.8 mm at 20° during valgus stress testing. Pellegrini-Stieda syndrome can also be seen on AP radiographs. This finding is due to calcification of the sMCL (heterotopic ossification) caused by the chronic tear of the ligament. MRI Magnetic resonance imaging (MRI) can be helpful in assessing for a ligamentous injury to the<unk>  side of the<unk> . Milewski et al. has found that grade I to III classification can be seen on MRI. With a high-quality image (1.5 tesla or 3 tesla magnet) and no previous knowledge of the patient's history, musculoskeletal radiologists were able to accurately diagnose<unk> <unk>  injury 87% of the time. MRI can also show associated bone bruises on the lateral side of the<unk> , which one study shows, happen in almost half of<unk> .<unk>  MRIs should be avoided for<unk>  pain without mechanical symptoms or effusion, and upon non-successful results from a functional rehabilitation program.
Medial knee injuries
Back strain
Elbow fracture
High ankle sprain
Ankle fracture
Facet syndrome
Knee dislocation
Patella fracture