Injectable hydrogels have been utilized in therapies related to joints. Using biocompatible, tunable hydrogel systems, they may be applied without surgery to repair or regenerate a joint. They can incorporate therapeutic agents to deliver them immediately or locally into the affected tissues. Natural and synthetic polymers can be used to create these hydrogel systems that will imitate the extracellular matrix (ECM) in cartilage and allow controlled release of bioactive additives such as growth factors and even stem cells. Other innovative examples include the advent of an "intelligent" thermos-responsive and pH-responsive hydrogel, which dynamically changes in response to its environment to provide a targeted treatment. Preclinical trials have proven that hydrogels indeed facilitate cartilage repair under inflammatory conditions and will eventually be developed into clinical trials. Such advances, however, can be seen only at the very beginning of the road given existing roadblocks such as mechanical strength, biocompatibility, and scale-up. Future directions include bringing more multi-functionality into hydrogels, personalized therapies, and solid clinical validation to bridge the parlance gap between laboratory innovation and real-world application. This review offers deeper insights into the properties, applications, challenges, and future directions of these injectable hydrogels concerning joint repair and the transformative potential they possess in regenerative medicine.