Undisplaced fracture can usually be treated by casting. Even some displaced fractures can be treated with casting as long as a person can straighten their leg without help. Typically the leg is immobilized in a straight position for the first three weeks and then increasing degrees of bending are allowed.

Plica syndrome treatment focuses on decreasing inflammation of the synovial capsule. A nonsteroidal anti-inflammatory drug (NSAID) is often used in conjunction with therapeutic exercise and modalities. Iontophoresis and phonophoresis have been utilized successfully against inflammation of the plica and synovial capsule. Failing these, surgical removal of the plica of the affected knee may be necessary.

In the absence of cartilage damage, pain at the front of the knee due to overuse can be managed with a combination of RICE (rest, ice, compression, elevation), anti-inflammatory medications, and physiotherapy.

Usually chondromalacia develops without swelling or bruising and most individuals benefit from rest and adherence to an appropriate physical therapy program. Allowing inflammation to subside while avoiding irritating activities for several weeks is followed by a gradual resumption. Cross-training activities such as swimming, strokes other than the breaststroke, can help to maintain general fitness and body composition. This is beneficial until a physical therapy program emphasizing strengthening and flexibility of the hip and thigh muscles can be undertaken. Use of nonsteroidal anti-inflammatory medication is also helpful to minimize the swelling amplifying patellar pain. Treatment with surgery is declining in popularity due to positive non-surgical outcomes and the relative ineffectiveness of surgical intervention.

Treatment may be with or without surgery, depending on the type of fracture.

The choice of surgical versus non-surgical treatments for osteochondritis dissecans is controversial. Consequently, the type and extent of surgery necessary varies based on patient age, severity of the lesion, and personal bias of the treating surgeon—entailing an exhaustive list of suggested treatments. A variety of surgical options exist for the treatment of persistently symptomatic, intact, partially detached, and completely detached OCD lesions. Post-surgery reparative cartilage is inferior to healthy hyaline cartilage in glycosaminoglycan concentration, histological, and immunohistochemical appearance. As a result, surgery is often avoided if non-operative treatment is viable.

Two types of treatment options are typically available:

- Surgery

- Conservative treatment (rehabilitation and physical therapy)

Surgery may impede normal growth of structures in the knee, so doctors generally do not recommend knee operations for young people who are still growing. There are also risks of complications, such as an adverse reaction to anesthesia or an infection.

When designing a rehabilitation program, clinicians consider associated injuries such as chipped bones or soft tissue tears. Clinicians take into account the person's age, activity level, and time needed to return to work and/or athletics. Doctors generally only recommend surgery when other structures in the knee have sustained severe damage, or specifically when there is:

- Concurrent osteochondral injury

- Continued gross instability

- Palpable disruption of the medial patellofemoral ligament and the vastus medialis obliquus

- High-level athletic demands coupled with mechanical risk factors and an initial injury mechanism not related to contact

Supplements like glucosamine and NSAIDs can be used to minimize bothersome symptoms.

If non-surgical measures are unsuccessful, drilling may be considered to stimulate healing of the subchondral bone. Arthroscopic drilling may be performed by using an antegrade (from the front) approach from the joint space through the articular cartilage, or by using a retrograde (from behind) approach through the bone outside of the joint to avoid penetration of the articular cartilage. This has proven successful with positive results at one-year follow-up with antegrade drilling in nine out of eleven teenagers with the juvenile form of OCD, and in 18 of 20 skeletally immature people (follow-up of five years) who had failed prior conservative programs.

Steroid injections are helpful in the short term (first approximately 4 weeks) however, their long term effectiveness is not known, and quality of evidence for its use remains poor and controversial.

Other, more conservative and non-surgical, treatment options available for the management and treatment of tendinopathy include: rest, ice, massage therapy, eccentric exercise, NSAIDs, ultrasound therapy, LIPUS, electrotherapy, taping, sclerosing injections, blood injection, glyceryl trinitrate patches, and (ESWT) extracorporeal shockwave therapy. Studies with a rat model of fatigue-damaged tendons suggested that delaying exercise until after the initial inflammatory stage of repair could promote remodelling more rapidly. There is insufficient evidence on the routine use of injection therapies (Autologous blood, Platelet-rich plasma, Deproteinised haemodialysate, Aprotinin, Polysulphated glycosaminoglycan, Corticosteroid, Skin derived fibroblasts etc.) for treating Achilles tendinopathy. As of 2014 there was insufficient evidence to support the use of platelet-rich therapies for treating musculoskeletal soft tissue injuries such as ligament, muscle and tendon tears and tendinopathies.

An effective rehabilitation program reduces the chances of reinjury and of other knee-related problems such as patellofemoral pain syndrome and osteoarthritis. Rehabilitation focuses on maintaining strength and range of motion to reduce pain and maintain the health of the muscles and tissues around the knee joint.

A Cochrane review of low-intensity pulsed ultrasound to speed healing in newly broken bones found insufficient evidence to justify routine use. Other reviews have found tentative evidence of benefit. It may be an alternative to surgery for established nonunions.

Vitamin D supplements combined with additional calcium marginally reduces the risk of hip fractures and other types of fracture in older adults; however, vitamin D supplementation alone did not reduce the risk of fractures.

Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used to treat PFPS, however there is only very limited evidence that they are effective. NSAIDs may reduce pain in the short term, overall however, after three months pain is not improved. There is no evidence that one type of NSAID is superior to another in PFPS, and therefore some authors have recommended that the NSAID with fewest side effects and which is cheapest should be used.

Glycosaminoglycan polysulfate (GAGPS) inhibits proteolytic enzymes and increases synthesis and degree of polymerization of hyaluronic acid in synovial fluid. There is contradictory evidence that it is effective in PFPS.

Treatment is generally conservative with rest, ice, and specific exercises being recommended. Simple pain killers may be used if required such as acetaminophen (paracetamol) or ibuprofen. Typically symptoms resolve as the growth plate closes. Physiotherapy is generally recommended once the initial symptoms have improved to prevent recurrence. Surgery may rarely be used in those who have stopped growing yet still have symptoms.

The scientific consensus is that surgery should be avoided except in very severe cases in which conservative treatments fail. The majority of individuals with PFPS receive nonsurgical treatment.

Persons with knock knees often have collapsed inner arches of their feet, and their inner ankle bones are generally lower than their outer ankle bones. Adults with uncorrected genu valgum are typically prone to injury and chronic knee problems such as chondromalacia and osteoarthritis. These in turn can cause severe pain and problems in walking.

It is normal for children to have knock knees between the ages of two and five years of age, and almost all of them resolve as the child grows older. If symptoms are prolonged and pronounced or hereditary, doctors often use orthotic shoes or leg braces at night to gently move a child's leg back into position. If the condition persists and worsens later in life, surgery may be required to relieve pain and complications resulting from severe or hereditary genu valgum. Available surgical procedures include adjustments to the lower femur and total knee replacement (TKR).

Weight loss and substitution of high-impact for low-impact exercise can help slow progression of the condition. With every step, the patient's weight places a distortion on the knee toward a knocked knee position, and the effect is increased with increased angle or increased weight. Even in the normal knee position, the femurs function at an angle because they connect to the hip girdle at points much further apart than they connect at the knees.

Physical therapy is generally of benefit to people with knock knees. To correct knock knees, the entire leg must be treated, especially:

1. Activating and developing the arches of the feet,

2. Waking up the outer leg muscles (abductors), and

3. Learning how to move the inner ankle bone inwards towards the outer ankle bone, and upwards towards the knee.

Working with a physical medicine specialist such as a physiatrist, or a physiotherapist may assist a patient learning how to improve outcomes and use the leg muscles properly to support the bone structures. Alternative or complementary treatments may include certain procedures from Iyengar Yoga or the Feldenkrais Method.

Rarely, the bone malformation underlying knock knees can be traced to a lack of nutrition necessary for bone growth, which can cause conditions such as rickets (lack of bone nutrients, especially dietary vitamin D and calcium), or scurvy (lack of vitamin C). The correction of the underlying vitamin deficiency may restore a more normal progression of bone growth.

Surgical methods of treating fractures have their own risks and benefits, but usually surgery is performed only if conservative treatment has failed, is very likely to fail, or likely to result in a poor functional outcome. With some fractures such as hip fractures (usually caused by osteoporosis), surgery is offered routinely because non-operative treatment results in prolonged immobilisation, which commonly results in complications including chest infections, pressure sores, deconditioning, deep vein thrombosis (DVT), and pulmonary embolism, which are more dangerous than surgery. When a joint surface is damaged by a fracture, surgery is also commonly recommended to make an accurate anatomical reduction and restore the smoothness of the joint.

Infection is especially dangerous in bones, due to the recrudescent nature of bone infections. Bone tissue is predominantly extracellular matrix, rather than living cells, and the few blood vessels needed to support this low metabolism are only able to bring a limited number of immune cells to an injury to fight infection. For this reason, open fractures and osteotomies call for very careful antiseptic procedures and prophylactic use of antibiotics.

Occasionally, bone grafting is used to treat a fracture.

Sometimes bones are reinforced with metal. These implants must be designed and installed with care. "Stress shielding" occurs when plates or screws carry too large of a portion of the bone's load, causing atrophy. This problem is reduced, but not eliminated, by the use of low-modulus materials, including titanium and its alloys. The heat generated by the friction of installing hardware can accumulate easily and damage bone tissue, reducing the strength of the connections. If dissimilar metals are installed in contact with one another (i.e., a titanium plate with cobalt-chromium alloy or stainless steel screws), galvanic corrosion will result. The metal ions produced can damage the bone locally and may cause systemic effects as well.

One of the main ways to prevent OSD is to check the participant's flexibility in their quadriceps and hamstrings. Lack of flexibility in these muscles can be direct risk indicator for OSD. Muscles can shorten, which can cause pain but this is not permanent. Stretches can help reduce shortening of the muscles. The main stretches for prevention of OSD focus on the hamstrings and quadriceps.

Early stages may be treated conservatively using the R.I.C.E methods.

1. Rest

2. Ice

3. Compression

4. Elevation

Exercises involving eccentric muscle contractions of the quadriceps on a decline board are strongly supported by extant literature. A physical therapist may also recommend specific exercises and stretches to strengthen the muscles and tendons, eg. cycling or swimming. Use of a strap for jumper's knee and suspension inlays for shoes may also reduce the problems.

Should this fail, autologous blood injection, or platelet-rich plasma injection may be performed and is typically successful though not as successful as high volume saline injection (Crisp "et al."). Uncommonly it may require surgery to remove myxoid degeneration in the tendon. This is reserved for patients with debilitating pain for 6–12 months despite conservative measures. Novel treatment modalities targeting the abnormal blood vessel growth which occurs in the condition are currently being investigated.

New research shows that knee operations in most cases have no better effects than exercise programs, and that most knee operations thus can be avoided.

Non-septic prepatellar bursitis can be treated with rest, the application of ice to the affected area, and anti-inflammatory drugs, particularly ibuprofen. Elevation of the affected leg during rest may also expedite the recovery process. Severe cases may require fine-needle aspiration of the bursa fluid, sometimes coupled with cortisone injections. However, some studies have shown that steroid injections may not be an effective treatment option. After the bursitis has been treated, rehabilitative exercise may help improve joint mechanics and reduce chronic pain.

Opinions vary as to which treatment options are most effective for septic prepatellar bursitis. McAfee and Smith recommend a course of oral antibiotics, usually oxacillin sodium or cephradine, and assert that surgery and drainage are unnecessary. Wilson-MacDonald argues that oral antibiotics are "inadequate", and recommends intravenous antibiotics for managing the infection. Some authors suggest surgical irrigation of the bursa by means of a subcutaneous tube. Others suggest that bursectomy may be necessary for intractable cases; the operation is an outpatient procedure that can be performed in less than half an hour.

Although surgery has a role in repairing traumatic injuries and broken bones, surgeries such as arthroscopic lavage do not provide significant or lasting improvements to either pain or function to people with degenerative knee pain, and therefore should almost never be performed. Degenerative knee pain is pain caused by wear and tear, such as osteoarthritis or a meniscal tear. Effective treatments for degenerative knee pain include physical therapy exercises, pain-reducing drugs such as ibuprofen, knee replacement surgery, and weight loss in people who are overweight.

Treatment of medial knee injuries varies depending on location and classification of the injuries. The consensus of many studies is that isolated grade I, II, and III injuries are usually well suited to non-operative treatment protocols. Acute grade III injuries with concomitant multiligament injuries or knee dislocation involving medial side injury should undergo surgical treatment. Chronic grade III injuries should also undergo surgical treatment if the patient is experiencing rotational instability or side-to-side instability.

Appropriate treatment for lameness depends on the condition diagnosed, but at a minimum it usually includes rest or decreased activity and anti-inflammatory medications. Other treatment options, such as corrective shoeing, joint injections, and regenerative therapies, are pursued based on the cause of lameness and the financial limits of the owner. Consultation with a veterinarian is generally recommended, even for mild cases, as some types of lameness may worsen if not properly diagnosed and treated.

Treatment of posterolateral corner injuries varies with the location and grade of severity of the injuries. Patients with grade I and II (partial) injuries to the posterolateral corner can usually be managed conservatively. Studies have reported that patients with grade III (complete) injuries do poorly with conservative management and typically will require surgical intervention followed by rehabilitation.

Treatment for NPS varies depending on the symptoms observed.

- Perform screening for renal disease and glaucoma, surgery, intensive physiotherapy, or genetic counseling.

- ACE inhibitors are taken to treat proteinuria and hypertension in NPS patients.

- Dialysis and renal transplant.

- Physical therapy, bracing and analgesics for joint pain.

- Other surgery treatments such as patella realignment, joint replacement, and the cutting away of the head of radius.

Rehabilitation protocols for post-op patients with repaired or reconstructed posterolateral corner injuries focus on strengthening and achieving full range of motion. Similar to nonoperative treatments, the patient is non-weightbearing for 6 weeks followed by a return to partial weight-bearing on crutches. Range of motion exercises begin first at 1 to 2 days postoperatively, followed by progressive strength training. Patients can typically begin riding a stationary bike and using a quadriceps machine around 6 to 8 weeks, but isolated hamstring exercises should be avoided for a minimum of 4 months postoperatively. Patients can progress to leg presses after 6 weeks, but the weight should be very light. Jogging and more aggressive strength training can begin around 4 – 6 months at the surgeon and physical therapists discretion. Patients should not be casted after surgery unless absolutely necessary.

Treatment of the unhappy triad usually requires surgery. An ACL surgery is common and the meniscus can be treated during the surgery as well. The MCL is rehabilitated through time and immobilization. Physical therapy after the surgery and the use of a knee brace help speed up the healing process.

A typical surgery for a blown knee includes:

- Patellar tendon autograft (An autograft is a graft that comes from the patient)

- Hamstring tendon autograft

- Quadriceps tendon autograft

- Allograft (taken from a cadaver) patellar tendon, Achilles tendon, semitendinosus, gracilis, or posterior tibialis tendon

The goal of reconstruction surgery is to prevent instability and restore the function of the torn ligament, creating a stable knee. There are certain factors that the patient must consider when deciding for or against surgery.